A member of the Cambodian royal family, he disappeared during the political purges carried out by the Communist Party of Cambodia (the Khmer Rouge) after it came to power.
Phurissara went on to join the Sangkum and serve as the Cambodian Foreign Minister during the later 1960s, in a period when Sihanouk was strengthening ties with China and other communist nations.
After Sihanouk was deposed by his Prime Minister, General Lon Nol, in the Cambodian coup of 1970, he set up a government-in-exile, the GRUNK, incorporating his former communist opponents, the Khmer Rouge.
They dispatched Phurissara, along with Ieng Sary, to persuade him to change his mind, but Sihanouk refused:[3] the Khmer Rouge cadres Khieu Samphan and Saloth Sar, the latter now using the name Pol Pot, took over leadership as Head of State and Prime Minister.
According to family members physically present at the time, sometime in April 1978 (exact date can not be ascertained) a Khmer Rouge military truck arrived at the location where Prince Phurissara had been assigned to live.