Marty McFly is a fictional character, the lead character in the Back to the Future motion picture trilogy, played by actor Michael J. Fox.

Marty was born in 1968, the youngest of 3 children to George McFly and Lorraine Baines McFly. He has a brother Dave, sister Linda and girlfriend Jennifer Parker. His best friend is mad scientist Doc Brown, who invented a time machine that was built into a DeLorean sports car in 1985. Marty and Doc had many adventures in this time machine, visiting 1955, 2015, an alternate 1985 and 1885 before finally returning home.

Marty plays lead guitar in a rock and roll band called the Pinheads and likes listening to Huey Lewis and the News and Eddie Van Halen. He is a good skateboarder (and hoverboarder in the future).

Although Marty improved his father's life by teaching him not to be afraid of a fight in the first movie, this becomes Marty's character flaw in parts 2 and 3. Marty was too eager to fight or take dares whenever someone called him "chicken", which caused him to break his guitar-playing hand in an automobile race in 1985 and ruined his dream of becoming a rock star. In the future, he has married Jennifer and had 2 kids, Marlene and Marty McFly Jr, but none of them were really happy. Upon returning from 1885 at the end of part 3, Marty no longer gets angry when he is called "chicken" and avoids the accident, leaving his future unwritten but hopeful.

Marty McFly resides in Hill Valley, California.