<?xml version="1.0" ?>
<informationTable xsi:schemaLocation="http://www.sec.gov/edgar/document/thirteenf/informationtable eis_13FDocument.xsd" xmlns="http://www.sec.gov/edgar/document/thirteenf/informationtable" xmlns:n1="http://www.sec.gov/edgar/document/thirteenf/informationtable" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <infoTable>
    <nameOfIssuer>ALIBABA GROUP HLDG LTD</nameOfIssuer>
    <titleOfClass>SPONSORED ADS</titleOfClass>
    <cusip>01609W102</cusip>
    <value>257588</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1411830</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>1411830</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>APELLIS PHARMACEUTICALS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>03753U106</cusip>
    <value>50304</value>
    <shrsOrPrnAmt>
      <sshPrnamt>2579708</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>2579708</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>ARCUS BIOSCIENCES INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>03969F109</cusip>
    <value>5308</value>
    <shrsOrPrnAmt>
      <sshPrnamt>425000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>425000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>ARVINAS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>04335A105</cusip>
    <value>9225</value>
    <shrsOrPrnAmt>
      <sshPrnamt>625000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>625000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>BEIGENE LTD</nameOfIssuer>
    <titleOfClass>SPONSORED ADR</titleOfClass>
    <cusip>07725L102</cusip>
    <value>585810</value>
    <shrsOrPrnAmt>
      <sshPrnamt>4437953</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>4437953</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>BILIBILI INC</nameOfIssuer>
    <titleOfClass>SPONS ADS REP Z</titleOfClass>
    <cusip>090040106</cusip>
    <value>65420</value>
    <shrsOrPrnAmt>
      <sshPrnamt>3452231</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>3452231</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>BLUEPRINT MEDICINES CORP</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>09627Y109</cusip>
    <value>119956</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1498516</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>1498516</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>BRIGHT SCHOLAR ED HLDGS LTD</nameOfIssuer>
    <titleOfClass>SPONSORED ADS</titleOfClass>
    <cusip>109199109</cusip>
    <value>41213</value>
    <shrsOrPrnAmt>
      <sshPrnamt>3985797</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>3985797</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>CHINA BIOLOGIC PRODS HLDGS I</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>G21515104</cusip>
    <value>251047</value>
    <shrsOrPrnAmt>
      <sshPrnamt>2751200</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>2751200</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>EIDOS THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>28249H104</cusip>
    <value>4188</value>
    <shrsOrPrnAmt>
      <sshPrnamt>178600</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>178600</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>ENSTAR GROUP LIMITED</nameOfIssuer>
    <titleOfClass>SHS</titleOfClass>
    <cusip>G3075P101</cusip>
    <value>94567</value>
    <shrsOrPrnAmt>
      <sshPrnamt>543487</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>543487</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>FACEBOOK INC</nameOfIssuer>
    <titleOfClass>CL A</titleOfClass>
    <cusip>30303M102</cusip>
    <value>196628</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1179600</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>1179600</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>FANG HLDGS LTD</nameOfIssuer>
    <titleOfClass>ADR</titleOfClass>
    <cusip>30711Y102</cusip>
    <value>2025</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1500000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>1500000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>FIBROGEN INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>31572Q808</cusip>
    <value>108879</value>
    <shrsOrPrnAmt>
      <sshPrnamt>2003287</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>2003287</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>G1 THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>3621LQ109</cusip>
    <value>15761</value>
    <shrsOrPrnAmt>
      <sshPrnamt>949431</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>949431</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>GOSSAMER BIO INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>38341P102</cusip>
    <value>20316</value>
    <shrsOrPrnAmt>
      <sshPrnamt>937500</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>937500</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>IQIYI INC</nameOfIssuer>
    <titleOfClass>SPONSORED ADS</titleOfClass>
    <cusip>46267X108</cusip>
    <value>300375</value>
    <shrsOrPrnAmt>
      <sshPrnamt>12557488</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>12557488</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>JD COM INC</nameOfIssuer>
    <titleOfClass>SPON ADR CL A</titleOfClass>
    <cusip>47215P106</cusip>
    <value>453493</value>
    <shrsOrPrnAmt>
      <sshPrnamt>15041243</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>15041243</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>KINIKSA PHARMACEUTICALS LTD</nameOfIssuer>
    <titleOfClass>COM CL A</titleOfClass>
    <cusip>G5269C101</cusip>
    <value>33156</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1835888</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>1835888</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>LINE CORP</nameOfIssuer>
    <titleOfClass>SPONSORED ADR</titleOfClass>
    <cusip>53567X101</cusip>
    <value>42525</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1207763</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>1207763</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>MELCO RESORTS AND ENTMT LTD</nameOfIssuer>
    <titleOfClass>ADR</titleOfClass>
    <cusip>585464100</cusip>
    <value>99299</value>
    <shrsOrPrnAmt>
      <sshPrnamt>4395700</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>4395700</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>MONDELEZ INTL INC</nameOfIssuer>
    <titleOfClass>CL A</titleOfClass>
    <cusip>609207105</cusip>
    <value>150482</value>
    <shrsOrPrnAmt>
      <sshPrnamt>3014473</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>3014473</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>MYOKARDIA INC</nameOfIssuer>
    <titleOfClass>COM</titleOfClass>
    <cusip>62857M105</cusip>
    <value>50742</value>
    <shrsOrPrnAmt>
      <sshPrnamt>975987</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>975987</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>NEW ORIENTAL ED &amp; TECH GRP I</nameOfIssuer>
    <titleOfClass>SPON ADR</titleOfClass>
    <cusip>647581107</cusip>
    <value>252</value>
    <shrsOrPrnAmt>
      <sshPrnamt>2800</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>2800</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>PINDUODUO INC</nameOfIssuer>
    <titleOfClass>SPONSORED ADS</titleOfClass>
    <cusip>722304102</cusip>
    <value>77676</value>
    <shrsOrPrnAmt>
      <sshPrnamt>3132096</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>3132096</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>PUXIN LTD</nameOfIssuer>
    <titleOfClass>ADS</titleOfClass>
    <cusip>74704P108</cusip>
    <value>874</value>
    <shrsOrPrnAmt>
      <sshPrnamt>126145</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>126145</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>SEA LTD</nameOfIssuer>
    <titleOfClass>SPONSORED ADS</titleOfClass>
    <cusip>81141R100</cusip>
    <value>101136</value>
    <shrsOrPrnAmt>
      <sshPrnamt>4300000</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>4300000</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>SOHU COM INC</nameOfIssuer>
    <titleOfClass>SPONSORED ADS</titleOfClass>
    <cusip>83410S108</cusip>
    <value>13298</value>
    <shrsOrPrnAmt>
      <sshPrnamt>802034</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>802034</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>TAL EDUCATION GROUP</nameOfIssuer>
    <titleOfClass>SPONSORED ADS</titleOfClass>
    <cusip>874080104</cusip>
    <value>411689</value>
    <shrsOrPrnAmt>
      <sshPrnamt>11410453</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>11410453</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
  <infoTable>
    <nameOfIssuer>TENCENT MUSIC ENTMT GROUP</nameOfIssuer>
    <titleOfClass>SPON ADS</titleOfClass>
    <cusip>88034P109</cusip>
    <value>26616</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1470491</sshPrnamt>
      <sshPrnamtType>SH</sshPrnamtType>
    </shrsOrPrnAmt>
    <investmentDiscretion>SOLE</investmentDiscretion>
    <votingAuthority>
      <Sole>1470491</Sole>
      <Shared>0</Shared>
      <None>0</None>
    </votingAuthority>
  </infoTable>
</informationTable>
