Raised by his father, Ohno began training full-time in 1996. He has been the face of short track in the United States since winning his medals at the 2002 Winter Olympics. At the age of 14, he became the youngest U.S. national champion in 1997 and was the reigning champion from 2001–2009, winning the title a total of 12 times. In December 1999, he became the youngest skater to win a World Cup event title, and became the first American to win a World Cup overall title in 2001, which he won again in 2003 and 2005. He won his first overall World Championship title at the 2008 championships.
Ohno's accolades and accomplishments include being the United States Olympic Committee's Male Athlete of the Month in October 2003 and March 2008, the U.S. Speedskating's Athlete of the Year for 2003, and was a 2002, 2003 and 2006 finalist for the Sullivan Award, which recognizes the best amateur athlete in the United States. Since gaining recognition through his sport, Ohno has worked as a motivational speaker, philanthropist, started a nutritional supplement business called 8 Zone, and in 2007, competed on and won the reality TV show Dancing with the Stars. Ohno later became host of a revival of Minute to Win It on Game Show Network and served as a commentator for NBC's coverage of the 2014 Winter Games in Sochi and the 2018 Winter Games in Pyeongchang.
Ohno was born in Seattle, Washington, to a Japanese-born father, Yuki Ohno (大野 幸 Ōno Yuki) and a European American mother, Jerrie Lee. He attended Saghalie Junior High in Federal Way, Washington. Ohno's parents divorced when he was an infant, and he was raised in Seattle by his father. He has had little contact with his biological mother and as of 2002 had expressed no interest in knowing her or his older half-brother. Ohno's father, a hair stylist and owner of the salon Yuki's Diffusion, often worked 12-hour shifts, and with no family in the United States, found it hard to balance career and family. His father chose to name his son Apolo after the Greek words apo, which means to "steer away from" and lo, which means "look out; here he comes."
When Ohno was very young, his father meticulously researched childcare providers to care for his son during his long work hours. As Apolo grew older, his father became concerned his son would become a latchkey kid, so Yuki got his son involved with competitive swimming and quad-speed roller skating at age 6. He later switched from the instruction of Benton Redford, a National Champion, to a team in Federal Way, Washington called Pattison's Team Extreme and became a national inline speedskating champion and record holder himself. His father used inline speed skating to fill his spare time. Ohno's days were spent with morning swimming practices, followed by schooling, and finally skating practices in the afternoon.
When Ohno was 12, he won the Washington state championship in the breaststroke, but preferred inline speed skating over swimming. He has stated that by the time he turned 13 years of age he attended parties with older teenagers if he did not have competitions on the weekends. His father has stated that it was a struggle balancing his son's desire for independence while helping him reach his potential as a young athlete.