Yen Chia-kan, Chinese lawyer and politician, President of the Republic of China (died 1993)

Yen Chia-kan, also known as C. K. Yen, was a Chinese politician and chemist and the second president of the Republic of China (Taiwan) from 1975 to 1978. A Kuomintang politician, he succeeded Chiang Kai-shek as the second president of the Republic of China on 5 April 1975, being sworn in on 6 April 1975, and served out the remainder of Chiang's term until 20 May 1978. Yen was widely known as the "Father of the New Taiwan Dollar".

The president of the Republic of China, also known as the president of Taiwan, is the head of state of the Republic of China (Taiwan), as well as the commander-in-chief of the Republic of China Armed Forces. Before 1949 the position had the authority of ruling over Mainland China, but losing control of it after communist victory in the Chinese Civil War, the remaining jurisdictions of the ROC have been limited to Taiwan, Penghu, Kinmen, Matsu, and smaller islands.