Glen Edward Day (born November 16, 1965) is an American professional golfer who plays on the PGA Tour Champions.

Bass, an avid golfer and member at Pearl River Valley Country Club just outside Poplarville, started Glen playing golf when he was 2 to 3 years of age.

He graduated from Poplarville High School in 1983, attended the University of Oklahoma, then turned professional in 1988.

Day was the first golfer to win a professional tournament using the Nike Golf Ball by defeating Payne Stewart to win the 1999 MCI Classic played at the Sea Pines Plantation Harbor Town Golf Links, Hilton Head, South Carolina.

Day is one of the few golfers to receive a slow play penalty in a non-major (1995 Honda Classic).