Homer Jay Simpson is a character in the animated television series The Simpsons. He is voiced by Dan Castellaneta and first appeared on television in the Tracey Ullman Show short "Good Night". He is one of five members of the titular family and has become the most popular and influential character in the series. Homer embodies several American working class stereotypes: he is crude, overweight, incompetent, clumsy, thoughtless and a borderline alcoholic. Despite the suburban blue-collar routine of his life, he has had a number of remarkable experiences. He has occasionally displayed flashes of great intellect and fitness whenever the situation calls for it, and an integrity reflecting his own values, including a fierce devotion to and protectiveness of his family. Castellaneta describes him as "a dog trapped in a man's body. He's incredibly loyal—not entirely clean—but you gotta love him."

Homer was created by cartoonist Matt Groening and named after Groening's father. He made his television debut on April 19, 1987 in the Tracey Ullman short "Good Night". In the shorts and earlier episodes, his voice was an loose impression of Walter Matthau but eventually evolved into a more robust voice during the second and third season of the half-hour show, allowing Homer to cover a fuller range of emotions. Homer has since become one of the most influential fictional characters and has been described by the UK newspaper The Sunday Times as the greatest comedic creation of modern time. He has inspired an entire line of merchandise and his catchphrase, the annoyed grunt "D'oh!", has been included in the Oxford English Dictionary.