Gulman was born on July 17, 1970 in Peabody, Massachusetts, is a 1993 graduate of Boston College where he played football as a tight end, and is a former elementary school gym Teacher and substitute Teacher. He is Jewish. He was well known for trying out his stand-up routines on his high-school aged students before bringing them to the stage at night. He is 6' 6" tall.
On November 25, 2006, Gary Gulman starred in his own one-hour Comedy Central special entitled "Gary Gulman: Boyish Man". His second Comedy Central special aired on December 8, 2012 called "In This Economy?."
Gary also had a guest appearance on Inside Amy Schumer in May 2014 and also performed on the Pete Holmes show on June 12, 2014. He was a guest on Jimmy Pardo's podcast Never Not Funny (episode 1512) on October 23, 2014, and again (on episode 1918) on December 8, 2016.
On September 9, 2015, Gary appeared as a guest on FriendsLikeUs, a podcast hosted by fellow Comedian Marina Franklin.