He was born in New York City, grew up in Whittier, California, and studied film at California State University, Long Beach.
Minear was an assistant director on the film Platoon, and wrote episodes for several television series including The X-Files, Zorro, and Lois and Clark. He later wrote, executive-produced, and directed episodes of Strange World, Angel, Firefly, Wonderfalls, and The Inside (which he also created, with Howard Gordon). Minear had another series, Drive, airing on Fox in April 2007, however, it was canceled by the network after only four episodes. Drive was set to return with two additional episodes on July 4, 2007, but these were rescheduled to July 13 and then canceled. This continued his tradition of short-lived work on Fox. Minear often works with Joss Whedon, and his work is typically characterized by a sharp, black humor and an ability to portray characters who are sympathetic and understandable, but morally ambiguous. An example of this is Angel Season Two, where Minear wrote all of the key episodes in the "beige Angel" arc. In 2004 Tim Minear stated that he was hired to write a screenplay of The Moon Is a Harsh Mistress. In 2006 Minear had finished the script, which was being shopped around to various directors. In 2007 Minear received a pilot commitment from ABC for Miracle Man, a drama series for which the company engaged in a bidding war with Fox Broadcasting Company. The series was being produced by 20th Century Fox Television, with which Minear had signed in an overall deal.