Koo Vi Kyuin or Ku Wei-ch黱 (simplified Chinese: ???; traditional Chinese: ???; pinyin: G?W閕jun; Wade-Giles: Ku Wei-ch黱) (January 29; 1887 - November 14; 1985); often known by the Western name V.K. Wellington Koo; was a prominent diplomat under the Republic of China; representative to the Paris Peace Conference of 1919; Ambassador to France; Great Britain; and the United States; participant in founding the League of Nations and the United Nations; and judge on the International Court of Justice at the Hague from 1957 to 1967.

Between October 1926 and June 1927; while serving as Minister of Foreign Affairs; Koo briefly held the concurrent positions of acting Premier and interim President of the Republic of China. Koo is the first and only Chinese head of state known to use a Western name publicly.