John Backderf (born October 31, 1959), also known as Derf or Derf Backderf, is an American cartoonist. He is most famous for his graphic novels, especially My Friend Dahmer, the international bestseller which won an Angoulême Prize, and earlier for his comic strip The City, which appeared in a number of alternative newspapers from 1990 to 2014. In 2006 Derf won the Robert F. Kennedy Journalism Award for cartooning. Backderf has been based in Cleveland, Ohio, for much of his career.

Backderf grew up in Richfield, Ohio, the son of a chemist. He attended Eastview Junior High and Revere High School, where one of his classmates was future serial killer Jeffrey Dahmer.

Backderf graduated high school in 1978, and attended the Art Institute of Pittsburgh for six months, before dropping out. The following year, he worked as a garbageman back in his hometown. Backderf then attended, and graduated from, Ohio State University with a BA in journalism. Backderf was immersed in the punk movement during the late 1970s and early 1980s.

He began as a political cartoonist, for the Ohio State Lantern, then professionally at The Evening Times, the evening counterpart of The Palm Beach Post, in West Palm Beach, Florida. He worked as a staff cartoonist at the Cleveland Plain Dealer in the late 80s. In the mid-1990s Backderf worked in the newsroom of the Akron Beacon Journal.

Backderf's comic strip The City appeared in 174 publications, mostly free weekly newspapers, starting with the now-defunct Cleveland Edition in 1990, including: The Village Voice, The Chicago Reader, Cleveland Scene, Miami New Times, Houston Press, Pittsburgh City Paper, The Providence Phoenix, and Washington City Paper. In 2014, Derf announced that he was discontinuing The City to focus on graphic novels.

Strips from The City were collected in The City: The World's Most Grueling Comic Strip (SLG Publishing, 2003) and a four-volume series of comic books, True Stories (Alternative Comics, 2015, 2016, 2018).

Backderf wrote Punk Rock & Trailer Parks (SLG Publishing, 2010), a 152-page graphic novel set in 1980, during the punk rock heyday in Akron, Ohio, a music scene that produced such acts as Devo, Chrissie Hynde, and The Cramps. Punk Rock & Trailer Parks is a fictional story that follows one remarkable young man named Otto who, through talent, wits and sheer chutzpah becomes a star in the Rubber City punk scene and has memorable meetings with underground luminaries of the day, including Wendy O. Williams, Stiv Bators, Lester Bangs, and The Clash. Punk Rock & Trailer Parks was featured in the 2010 edition of Best American Comics (Houghton Mifflin).

My Friend Dahmer (Abrams Comic Arts, 2012) is the culmination of a comic book project first started in 1994, shortly after Jeffrey Dahmer was murdered in prison. The book is the true story of how a young Backderf befriended his high-school classmate Dahmer, a troubled teenager prone to odd behavior, because he and his friends were amused by Dahmer's antics; the book also depicts some of Dahmer's increasingly morbid behavior that Backderf was unaware of at the time, culminating in Backderf and his friends falling away from Dahmer when he becomes more disturbing than funny.