FORM 6-K

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

Report of Foreign Private Issuer

Pursuant to Rule 13a-16 or 15d-16 of

The Securities Exchange Act of 1934

 For the month of May 2019

(Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.)

Form 20-F     X    Form 40-F _____

(Indicate by check mark whether the registrant by furnishing the information contained in this form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934. )

Yes ____ No   X   

(If "Yes" is marked, indicate below the file number assigned to registrant in connection with Rule 12g3-2(b): 82-__________. )

N/A

Huaneng Power International, Inc.

Huaneng Building,

6 Fuxingmennei Street,

Xicheng District,

Beijing, 100031 PRC

This Form 6-K consists of:

An announcement regarding issue of super short-term debentures of Huaneng Power International, Inc. (the Registrant”), made by the Registrant on May 14, 2019.

Hong Kong Exchanges and Clearing Limited and The Stock Exchange of Hong Kong Limited take no responsibility for the contents of this announcement, make no representation as to its accuracy or completeness and expressly disclaim any liability whatsoever for any loss howsoever arising from or in reliance upon the whole or any part of the contents of this announcement.

(Stock Code: 902)

OVERSEAS REGULATORY ANNOUNCEMENT

ISSUE OF SUPER SHORT-TERM DEBENTURES

This announcement is made pursuant to Rule 13.10B of the Rules Governing the Listing of Securities on The Stock Exchange of Hong Kong Limited (the “Listing Rules”).

As resolved at the 2016 annual general meeting of Huaneng Power International, Inc. (the “Company”) held on 13 June 2017, the Company has been given a mandate to issue super short-term debentures (in either one or multiple tranches on rolling basis) with a principal amount of up to RMB32 billion (which means that the outstanding principal balance of the super short-term debentures in issue shall not exceed RMB32 billion at any time within the period as prescribed therein) in the PRC within 24 months from the date on which the shareholders’ approval was obtained.

The Company has recently completed the issue of the second tranche of the Company’s super short- term debentures for 2019 (the “Debentures”). The total issuing amount was RMB5 billion with a maturity period of 180 days whereas the unit face value is RMB100 and the interest rate is 2.30%.

Bank of Ningbo Co., Ltd. acts as the lead underwriter to form the underwriting syndicate for the Debentures, which were placed through book-building and issued in the domestic bond market among banks. The proceeds from the Debentures will be used to supplement the working capital of the headquarters of the Company, adjust debts structure and repay the debt financing instruments due.

The relevant documents in respect of the Debentures are posted on China Money and Shanghai Clearing House at websites of www.chinamoney.com.cn and www.shclearing.com, respectively.

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The Debentures do not constitute any transaction under Chapter 14 and Chapter 14A of the Listing Rules.

 By Order of the Board

 Huaneng Power International, Inc.

 Huang Chaoquan

 Company Secretary

As at the date of this announcement, the directors of the Company are:

Shu Yinbiao (Executive Director)	Yue Heng (Independent Non-executive Director)
Huang Jian (Non-executive Director)	Xu Mengzhou (Independent Non-executive Director)
Wang Yongxiang (Non-executive Director)	Liu Jizhen (Independent Non-executive Director)
Mi Dabin (Non-executive Director)	Xu Haifeng (Independent Non-executive Director)
Guo Hongbo (Non-executive Director)	Zhang Xianzhi (Independent Non-executive Director)
Cheng Heng (Non-executive Director)
Lin Chong (Non-executive Director)

14 May 2019

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the under-signed, thereunto duly authorized.

HUANENG POWER INTERNATIONAL, INC.
By  /s/ Huang Chaoquan
Name:	Huang Chaoquan
Title:	Company Secretary

Date:     May 14, 2019