UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16 UNDER

THE SECURITIES EXCHANGE ACT OF 1934

For the month of May 2015

Commission File Number: 001-33853

CTRIP.COM INTERNATIONAL, LTD.

99 Fu Quan Road

Shanghai 200335, People’s Republic of China

(Address of principal executive office)

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  o

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): o

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): o

SIGNATURES

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 undersigned, thereunto duly authorized.

Date: May 22, 2015

2

EXHIBIT INDEX

3

Exhibit 99.1

Ctrip Acquires Strategic Stake in eLong

SHANGHAI, May 22, 2015 — Ctrip.com International, Ltd. (NASDAQ: CTRP), a leading travel service provider of accommodation reservation, transportation ticketing, packaged tours and corporate travel management in China (“Ctrip” or the “Company”) today announced its investment in eLong, Inc. (NASDAQ: LONG) (“eLong”) through acquiring eLong shares from certain selling shareholders, including Expedia, Inc. (NASDAQ: EXPE) (“Expedia”), together with several other investors.  Ctrip acquired a 37.6% equity stake in eLong for a total purchase price of approximately $400 million.

In addition, Ctrip and Expedia have agreed to cooperate with each other to allow their respective customers to benefit from certain travel product offerings for specified geographic markets.

The transaction closed on May 22, 2015.

About Ctrip.com International, Ltd.

Ctrip.com International, Ltd. is a leading travel service provider of accommodation reservation, transportation ticketing, packaged tours, and corporate travel management in China. It is the largest online consolidator of accommodations and transportation tickets in China in terms of transaction volume. Ctrip enables business and leisure travelers to make informed and cost-effective bookings by aggregating comprehensive travel related information and offering its services through an advanced transaction and service platform consisting of its mobile apps, Internet websites and centralized, toll-free, 24-hour customer service center. Ctrip also helps customers book vacation packages and guided tours. In addition, through its corporate travel management services, Ctrip helps corporate clients effectively manage their travel requirements. Since its inception in 1999, Ctrip has experienced substantial growth and become one of the best-known travel brands in China.

For further information, please contact:

Investor Relations

Ctrip.com International, Ltd.
Tel: (+86) 21 3406 4880 X 12229
Email: iremail@ctrip.com