Peterson was born in Winnipeg and studied in Vancouver at the Kitsilano Secondary School. Along with the Sun, his work often appeared in Maclean's magazine, where he would illustrate the columns of Allan Fotheringham. He has also illustrated the covers of many of Fotheringham's books.
Peterson has published the following books:
The World According to Roy Peterson, containing selected cartoons from the 1970s, with commentary by Alan Fotheringham