After graduating high school Ross spent 20 years keeping medical records for the U.S. Air Force, which is where he first started painting. Ross was living in Florida early in his military career when the Air Force transferred him to Alaska, where he first saw the snow and mountains that later became recurring themes in his artwork; he developed his quick-painting technique in order to be able to create art for sale in brief daily work breaks. Having held military positions that required him to be, in his own words, "mean" and "tough," "the guy who makes you scrub the latrine, the guy who makes you make your bed, the guy who screams at you for being late to work," Ross decided that if he ever moved on from the military, "it wasn't going to be that way any more," and "vowing never to scream again." Ross discovered after beginning his sideline in painting that he was soon able to earn more from selling his work than from his Air Force position. After leaving the Air Force, he studied with William Alexander before becoming famous worldwide with his own television program.
Ross had a son, Steven, from his first marriage to Lydia. Steven occasionally appeared on The Joy of Painting and is a Bob Ross-certified instructor. Ross and Lydia's marriage ended in divorce in 1981. Ross married again, this time to Jane. Jane died of cancer in 1993.