Alison Bechdel (/ˈbɛkdəl/ ^ⓘ BEK-dəl; born September 10, 1960) is an American cartoonist. Originally known for the long-running comic strip Dykes to Watch Out For, she came to critical and commercial success in 2006 with her graphic memoir Fun Home. Fun Home was subsequently adapted as a musical, which won a Tony Award for Best Musical in 2015. In 2012, she released her second graphic memoir Are You My Mother? She was a 2014 recipient of the MacArthur "Genius" Award. She is also known for originating what would later be called the Bechdel test.

Bechdel was born in Lock Haven, Pennsylvania. She is the daughter of Helen Augusta (née Fontana) and Bruce Allen Bechdel. Her family was Roman Catholic. Her father was an army veteran who was stationed in West Germany. He was also a high school English teacher, working full-time and operating a funeral home part-time. Her mother was an actress and teacher. Both of her parents contributed to her career as a cartoonist. She has two brothers: Bruce "Christian" Bechdel II and John Bechdel, a keyboard player who has worked with many bands including Fear Factory, Ministry, Prong and Killing Joke. Bechdel left high school a year early and earned her A.A. in 1979 from Bard College at Simon's Rock. She graduated with a degree in studio arts and art history in 1981 from Oberlin College. After her father died in 1980, her mother sold the family house in Beech Creek, Pennsylvania, the small town where Bechdel grew up, and moved to Bellefonte, a less provincial small town near State College with her long-time partner Robert Fenichel.

Bechdel moved to Manhattan during the summer of 1981 and applied to several art schools, but was rejected and worked in many office jobs in the publishing industry.

She began Dykes to Watch Out For as a single drawing labeled "Marianne, dissatisfied with the morning brew: Dykes to Watch Out For, plate no. 27". An acquaintance recommended she send her work to WomaNews, a feminist newspaper, which published her first work in its June 1983 issue. Bechdel gradually moved from her early single-panel drawings to multi-paneled strips. Dykes to Watch Out For began this process, developing into a series of posters and postcards, allowing for people to have a look into the urban lesbian community. After a year, other outlets began running the strip.

In the first years, Dykes to Watch Out For consisted of unconnected strips without a regular cast or serialized storyline. However, its structure eventually evolved into a focus on following a set group of lesbian characters. In 1986, Firebrand Books published a collection of the strips to date. In 1987, Bechdel introduced her regular characters, Mo and her friends, while living in St. Paul, Minnesota. Dykes to Watch Out For is the origin of the "Bechdel test", intended as a joke, which has become a frequently used metric in cultural discussion of film. In 1988, she began a short-lived page-length strip about the staff of a queer newspaper, titled "Servants to the Cause", for The Advocate. Bechdel has also written and drawn autobiographical strips and has done illustrations for magazines and websites. The success of Dykes to Watch Out For allowed Bechdel to quit her day job in 1990 to work on the strip full-time.

In November 2006, Bechdel was invited to sit on the Usage Panel of the American Heritage Dictionary. In 2012, Bechdel was a Mellon Residential Fellow for Arts and Practice at the Richard and Mary L. Gray Center at the University of Chicago and co-taught "Lines of Transmission: Comics & Autobiography" with Professor Hillary Chute. On April 6, 2017, Bechdel was appointed as Vermont's third Cartoonist Laureate.

In 2014, she posted a comic strip based on her Fun Home! The Musical! After Donald Trump's election in 2016 as U.S. president she posted three new episodes of Dykes to Watch Out For: "Pièce de Résistance," "Postcards From the Edge," and "Things Fall Apart."

Bechdel became Professor in the Practice, English and Film & Media Studies at Yale University in 2024.