NONCONTROLLING INTEREST (Details)	12 Months Ended
Dec. 31, 2019 USD ($)	Dec. 31, 2019 CNY (¥)	Dec. 31, 2018 CNY (¥)	Dec. 31, 2017 CNY (¥)
Noncontrolling Interest
Net loss attributable to The9 Limited	$ (25,538,677)	¥ (177,795,168)	¥ (217,092,926)	¥ (118,165,850)
Transfers (to) from the noncontrolling interest
Change in The9 Limited's additional paid-in capital for adjustment on non-controlling interest as a result of issuance of common shares of Red 5 upon vesting of stock options and restricted shares	0	0	0	(7,060)
Change from net loss attributable to The9 Limited and transfers (to) from noncontrolling interests	$ (25,538,677)	¥ (177,795,168)	¥ (217,092,926)	(118,172,910)
Additional paid-in capital
Transfers (to) from the noncontrolling interest
Change in The9 Limited's additional paid-in capital for adjustment on non-controlling interest as a result of issuance of common shares of Red 5 upon vesting of stock options and restricted shares				¥ (7,060)

Change in noncontrolling interests.

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- Definition

Changes from Net Income Loss Attributable to Reporting Entity and Transfers from (to) Noncontrolling Interests

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities, and addition from assumption of issuance of common shares for dilutive potential common shares; of income (loss) available to common shareholders.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=117326831&loc=d3e1505-109256

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=117326831&loc=d3e1377-109256

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