Chbosky was born in Pittsburgh, Pennsylvania and raised in Upper St. Clair, Pennsylvania. He is the son of Fred, a consultant to CFO, and Lea Chbosky, a tax preparer, and is of Polish, Slovak, Irish and Scottish descent. As a teenager, Chbosky "enjoyed a good blend of the classics, horror, and fantasy." He was heavily influenced by J. D. Salinger's novel The Catcher in the Rye and the writing of F. Scott Fitzgerald and Tennessee Williams. Chbosky graduated from Upper St. Clair High School in 1988, around which time he met Stewart Stern, screenwriter of the 1955 James Dean film Rebel Without a Cause. Stern became Chbosky's "good friend and mentor", and proved a major influence on Chbosky's career.

In 1992, Chbosky graduated from the University of Southern California's screenwriting program. He wrote, directed, and acted in the 1995 independent film The Four Corners of Nowhere, which got Chbosky his first agent, was accepted by the Sundance Film Festival, and became one of the first films shown on the Sundance Channel. In the late 1990s, Chbosky wrote several unproduced screenplays, including ones titled Audrey Hepburn's Neck and Schoolhouse Rock.

In 1994, Chbosky was working on a "very different type of book" The Perks of Being a Wallflower when he wrote the line, "I guess that's just one of the perks of being a wallflower." Chbosky recalled that he "wrote that line. And stopped. And realized that somewhere in that [sentence] was the kid I was really trying to find." After several years of gestation, Chbosky began researching and writing The Perks of Being a Wallflower, an epistolary novel that follows the intellectual and emotional maturation of a teenager who uses the alias Charlie over the course of his freshman year of high school. The book is semi-autobiographical; Chbosky has said that he "relate[s] to Charlie[...]But my life in high school was in many ways different."

The book, Chbosky's first novel, was published by MTV Books in 1999, and was an immediate popular success with teenage readers; by 2000, the novel was MTV Books' best-selling title, and The New York Times noted in 2007 that it had sold more than 700,000 copies and "is passed from adolescent to adolescent like a hot potato". Wallflower also stirred up controversy due to Chbosky's portrayal of teen sexuality and drug use. Word Riot The book has been banned in several schools and appeared on the American Library Association's 2006 and 2008 lists of the 10 most frequently challenged books.

In 2000, Chbosky edited Pieces, an anthology of short stories. The same year, he worked with director Jon Sherman on a film adaptation of Michael Chabon's novel The Mysteries of Pittsburgh, though the project fell apart by August 2000. Chbosky wrote the screenplay for the 2005 film adaptation of the Broadway rock musical Rent, which received mixed reviews. Rent - Movie Reviews, Trailers, Pictures - Rotten Tomatoes In late 2005, Chbosky said that he was writing a film adaptation of The Perks of Being a Wallflower.

In the mid-2000s, Chbosky decided, on the advice of his agent, to begin looking for work in television in addition to film. Finding he "enjoyed the people [he met who were working] in television", Chbosky agreed to serve as co-creator, executive producer, and writer of the CBS serial television drama Jericho, which premiered in September 2006. The series revolves around the inhabitants of the fictional small town of Jericho, Kansas in the aftermath of several nuclear attacks. Chbosky has said the relationship between Jake Green, the main character, and his mother, reflected "me and my mother in a lot of ways". The first season of Jericho received lackluster ratings, and CBS canceled the show in May 2007. A grassroots campaign to revive the series convinced CBS to renew the series for a second season, which premiered on February 12, 2008, before being canceled once more in March 2008. Breaking News - Game Shows, Popular Reality Series, News Magazines, The Season Premieres Of Two Returning Scripted Programs, And The Debut Of A New Comedy Join Cbs'S Primetime Schedule In January And February | Thefutoncritic.Com

Chbosky resides in Los Angeles, California.