Sisowath Monireth was a Cambodian politician who served as the Prime Minister of Cambodia, during the French protectorate period, from 17 October 1945 to 15 December 1946. One of the most prominent members of the Sisowath line of the royal family at the time, he had earlier been passed over for the throne by the French authorities in favor of his nephew Norodom Sihanouk, whom they considered to be more pliable. The prince, however, remained heir to the throne under Sihanouk's reign.