The station was launched in 1957 by the city's daily newspaper, the Cornwall Standard Freeholder, with the call sign CKSF-FM. The newspaper also already owned AM sister station CKSF. Two years later, the stations were acquired by Stanley Shankman, the owner of CJSS-TV, and both changed their callsigns to CJSS as well.
Two years later, Shenkman sold his broadcast holdings. The TV station was sold to Ottawa's CJOH-TV, and the radio stations were sold to the local Émard family.
The radio stations were subsequently acquired by Tri Co Broadcasting in 1978, and CFLG adopted its current callsign. CFLG originally aired a beautiful music format which has since been updated to the current AC sound. They are now owned by Corus Entertainment, who acquired them in 2001.