Ryan Thomas Gosling was born in London, Ontario, the son of Thomas Ray Gosling, a travelling salesman for a paper mill, and Donna, a secretary. Both of his parents are of part French-Canadian descent, along with some German, English, Scottish, and Irish. Gosling's parents were Mormons, and Gosling has said that the religion influenced every aspect of their lives. However, he said he "never really could identify with [Mormonism]." Because of his father's work, they "moved around a lot" and Gosling lived in both Cornwall, Ontario, and Burlington, Ontario. His parents divorced when he was 13, and he and his older sister Mandi lived with their mother, an experience Gosling has credited with programming him "to think like a girl".
Gosling was educated at Gladstone Public School, Cornwall Collegiate and Vocational School and Lester B. Pearson High School. As a child, he watched Dick Tracy and was inspired to become an actor. He "hated" being a child, was bullied in elementary school and had no friends until he was "14 or 15". In grade one, having been heavily influenced by the action film First Blood, he took steak knives to school and threw them at other children during recess. This incident led to a suspension. He was unable to read and was evaluated for attention deficit hyperactivity disorder (ADHD), but was not diagnosed with it and, contrary to false reports, never took medication. His mother left her job and homeschooled him for a year. Gosling has said that homeschooling gave him "a sense of autonomy that I've never really lost". Gosling performed in front of audiences from an early age, encouraged by his sister being a performer. He and his sister sang together at weddings; he performed with Elvis Perry, his uncle's Elvis Presley tribute act, and was involved with a local ballet company. Performing boosted his self-confidence as it was the only thing he received praise for. He developed an idiosyncratic accent because, as a child, he thought having a Canadian accent did not sound "tough". He began to model his accent on that of Marlon Brando. He dropped out of high school at the age of 17 to focus on his acting career.