Cornell was born Christopher John Boyle on July 20, 1964, in Seattle, Washington, where he was raised. His parents are Edward F. Boyle, a pharmacist of Irish-Catholic background, and Karen Cornell, an accountant and psychic of Jewish background. After his parents' divorce when he was a teenager, Chris and his siblings adopted their mother's maiden name, Cornell, as their surname. Cornell was one of six children; he had two older brothers and three younger sisters. He attended Christ the King Catholic elementary school, where he performed for the first time in front of a crowd, singing the 1960s anti-war song "One Tin Soldier". He later attended Shorewood High School. When he was in seventh grade, his mother pulled him and his sister out of Catholic school; Cornell claimed because they were about to be expelled for being too inquisitive. Cornell recalled the episode in a 1994 interview: "With a religion like that, it's not designed for anyone to question. Being young people who have a natural curiosity and half a brain, you're going to start finding inconsistencies, which there are tons of in organized religion. We both sort of made it clear in classroom situations that we didn't get it. 'Explain this to me.' And they couldn't, so we started creating a lot of problems."
Cornell traced his musical influences back to Little Richard via The Beatles. He spent a two-year period between the ages of nine and eleven solidly listening to The Beatles after finding a large collection of Beatles records abandoned in the basement of a neighbor's house. He described himself at this age as a loner; he was able to deal with his anxiety around other people through rock music. During his teenage years, he spiraled into severe depression, dropped out of school, and almost never left the house. At the age of 12, he had access to alcohol, marijuana, LSD, psilocybin mushrooms and prescription drugs; he used them daily by 13, stopped for a year, but relapsed at age 15 for another year until he turned to music. At 14, he had a bad PCP experience and later suffered from panic disorder and agoraphobia.
Cornell took piano and guitar lessons as a child. He once explained that his mother saved his life when she bought him a snare drum, the instrument he adopted in beginning his path to become a rock musician. Before becoming a successful musician, he worked as a busboy, as a dishwasher, as a fish monger at a seafood wholesaler and was a sous-chef at Ray's Boathouse in Seattle.
In the early 1980s, Cornell was a member of a cover band called The Shemps, which featured bassist Hiro Yamamoto and performed around Seattle. After Yamamoto left The Shemps, the band recruited guitarist Kim Thayil. Cornell and Yamamoto stayed in contact, and after The Shemps broke up, the pair started jamming together, eventually bringing Thayil in to join them.