James Gregory "Greg" Keelor (born August 29, 1954) is a Canadian singer-songwriter and musician. He is best known as a member of the band Blue Rodeo, where he shares song writing and vocal duties with Jim Cuddy. Keelor has also released three solo albums and appeared as a guest musician on albums by Crash Vegas and Melissa McClelland. He participated, along with Rick White and members of The Sadies, in the supergroup The Unintended.

Keelor has been friends with Jim Cuddy since both attended North Toronto Collegiate Institute high school. When they both had finished University, they decided to form a band which they called the Hi-Fi's along with Jim Sublett on drums and Malcolm Schell playing bass. The band released a single in 1980 featuring "I Don't Know Why (You Love Me)" and on the B side "Look What You've Done". The record was not a big commercial success, though, and when they couldn't get a record deal in Toronto, they headed off to New York. A while after returning to Toronto from New York, Keelor and Cuddy formed Blue Rodeo.

Keelor is also a producer, having co-produced Blue Rodeo's Lost Together and solo-producing Cuff the Duke's albums Way Down Here and Morning Comes.

Keelor also composed an original soundtrack for the 2010 Canadian Western comedy Gunless.

In 2013, he was made an Officer of the Order of Canada along with Jim Cuddy, "for their contributions to Canadian music and for their support of various charitable causes".