| Honorific-Prefix: | His Royal Highness Prince |
| Sisowath Youtevong | |
| Native Name: | Central Khmer: ស៊ីសុវត្ថិ យុត្តិវង្ស |
| Office: | Prime Minister of Cambodia |
| Term Start: | 15 December 1946 |
| Term End: | 17 July 1947 |
| Predecessor: | Sisowath Monireth |
| Successor: | Sisowath Watchayavong |
| Office1: | Leader of the Democratic Party |
| Term Start1: | June 1946 |
| Term End1: | July 1947 |
| Birth Date: | 1913 |
| Birth Place: | Oudong, Cambodia, French Indochina |
| Death Date: | 17 July 1947 (aged 33–34) |
| Death Place: | Phnom Penh, Cambodia, French Indochina |
| Blank1: | House |
| Data1: | House of Sisowath |
| Parents: | Sisowath Chamraengvongs Sisowath Yubhiphan |
| Party: | Democratic |
| Otherparty: | French Section of the Workers' International |
| Spouse: | Dominique Laverne |
| Alma Mater: | University of Montpellier (PhD) |
| Children: | 2 |
Sisowath Youtevong (Central Khmer: អ្នកអង្គម្ចាស់ ស៊ីសុវត្ថិ យុត្តិវង្ស; 1913 – 17 July 1947) was a Cambodian prince, politician and mathematician, credited as the "Father of Cambodian Democracy",[1] and a member of the Democratic Party. He served as the fourth Prime Minister of Cambodia from December 1946 to July 1947. He was the first to be elected prime minister.
Sisowath Youtevong was born in 1913 in Udong, Cambodia, as the son of Prince Chamraengvongs (1870–1916) and Princess Sisowath Yubhiphan (1877–1967). He studied at a science university in France and received a certificate of mathematics in 1941.[2] He was also a member of the French Section of the Workers' International, the predecessor to the present-day Socialist Party. He would later go on to be elected as President of the newly founded Democratic Party of Cambodia in April 1946. Youtevong was the principal author of the constitution at that time, which was put to use on 6 May 1947. He led the Democratic Party to victory in the elections on 1 September 1946 and was sworn in as Prime Minister on 15 December 1946. Prince Sisowath Youtevong died on 17 July 1947, at Calmette Hospital, Phnom Penh, and was succeeded by Sisowath Watchayavong.
Sisowath Youtevong was married to a French woman named Dominique Laverne and had two daughters: SisowathKantara (born 1945) and Sisowath Lenanda (born 1946).