Pen Ran disappeared during the Khmer Rouge genocide of the late 1970s and her exact fate is unknown. Her younger sister Pen Ram said that she survived until the Vietnamese invasion of late 1978/early 1979 when the Khmer Rouge launched their final series of mass executions. Given the goal of the Khmer Rouge to remove foreign influences from Cambodian society, Pen Ran's individuality probably ensured her death. In a 2015 BBC documentary on the band Cambodian Space Project, who have covered many of Pen Ran's songs, it was alleged by an interview subject that she was tricked by the Khmer Rouge into performing one of her songs, after which she was led away and executed.