A high school dropout, Chong began his entertainment career when he co-founded The Shades, a Canadian rhythm and blues band for which he played guitar. He moved on to become a member of Bobby Taylor and the Vancouvers for whom he co-wrote a popular song entitled "Does Your Mama Know About Me". Chong honed his acting and comedy skills by forming City Works, an improvisational group where he first worked with Marin who was in Toronto avoiding the US draft.
Cheech and Chong enjoyed a major following throughout the 70s and early 80s. Their 1972 album "Big Bambu" became the largest-selling comedy recording of all time and held that record for many years. Their follow-up, "Los Cochinos", won the Grammy for Best Comedy Recording. They segued into films with the surprise hit "Cheech & Chong's Up in Smoke" (1978). Budgeted at a thrifty $2 million, the movie grossed $47.5 million domestically, making it the most profitable film released that year. "Up in Smoke" went on to earn more than $100 million worldwide. The success of this initial venture produced five subsequent "joint" film projects for the amusingly stoned duo. Chong co-wrote all of them with Marin and directed several.
After the team of Cheech and Chong had run its long successful course, both embarked on solo careers. Chong appeared in several films without Marin including 1990's "Far Out, Man!" (where Cheech made a fleeting cameo appearance). Chong wrote, directed, starred and composed songs for this underperforming story of a 60s hippy who comes out of hiding and rediscovers his family. Fittingly, Chong cast a number of his own family members in the production. He produced a busted sitcom pilot ("The Family Martinez", CBS 1986) starring Robert Beltran of "Star Trek: Voyager", and a short-lived comedy series ("Trial and Error", CBS 1988). Chong has also done a couple of guest shots, memorably as a well-cast old friend of the protagonist on "The George Carlin Show" (Fox, 1994). Semi-retired for much of the 90s, he returned to the screen for a supporting role in "National Lampoon's Senior Trip" (1995). Beginning in 1999, Chong had a recurring role on the popular Fox sitcom "That '70s Show" and as of the 2001-2002 season was bumped up to regular status.
Chong is the father of actor Rae Dawn Chong. He has said that biracial actor Marcus Chong, who portrayed Huey Newton in the Van Peebles' "Panther" (1995), has adopted his family and he therefore considers the younger Chong to be his "adopted" son.