Prince Phetsarath Ratanavongsa (Somdej Chao Maha Uparaja Pethsarath Ratanavongsa (Lao: ???????????? ??? ?????? ??????? ?????????) (19 January 1890 – 14 October 1959) was the 1st Prime Minister of Luang Phrabang in French Laos from 21 August 1941 to 10 October 1945, and Head of State of Laos between 12 October 1945 and 4 April 1946.