Sec Form 4 Filing - Dunde Yu @ Tuniu Corp - 2026-06-08

FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person Dunde Yu 2. Issuer Name and Ticker or Trading Symbol Tuniu Corp [ TOUR] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X __ Director _____ 10% Owner X __ Officer (give title below) _____ Other (specify below) Chief Executive Officer (Last) (First) (Middle) 12TH FLOOR, BUILDING 6-A, JUHUIYUAN 3. Date of Earliest Transaction (MM/DD/YY) 06/08/2026 (Street) NANJING210023 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) __ X __ Form filed by One Reporting Person _____ Form filed by More than One Reporting Person (City) (State) (Zip)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned 1.Title of Security (Instr. 3) 2. Transaction Date (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned ( e.g. , puts, calls, warrants, options, convertible securities) 1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5) 6. Date Exercisable and Expiration Date (MM/DD/YY) 7. Title and Amount of Underlying Securities (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4) Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares Option (Right to Buy) $ 3 06/08/2026 D 900,000 06/12/2018 06/12/2026 Class A Ordinary Share 900,000 ( 1 ) 0 I By Dragon Rabbit Capital Limited ( 2 ) Option (Right to Buy) $ 3 06/08/2026 A 900,000 06/12/2018 06/12/2027 Class A Ordinary Share 900,000 ( 1 ) 900,000 I By Dragon Rabbit Capital Limited ( 2 )

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other Dunde Yu 12TH FLOOR, BUILDING 6-A, JUHUIYUAN NANJING210023 X Chief Executive Officer Signatures /s/ Dunde Yu 06/10/2026 Signature of Reporting Person Date

Explanation of Responses:

( 1 )The two reported transactions involved an amendment of an outstanding option to extend the expiration date thereof by one year, resulting in the deemed cancellation of the original option for Section 16 purposes and the grant of a replacement option for Section 16 purposes. The option was originally granted on June 13, 2014 and is fully vested. ( 2 )Dragon Rabbit Capital Limited is wholly owned by Longtu Holdings Limited, a British Virgin Islands company which is wholly owned by a trust, of which Mr. Yu's family is the beneficiary.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

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