The Sixers had a three-game losing streak going into Saturday night's contest against Washington, and more had been expected from a team that signed free-agent forward Elton Brand to a five-year, $80 million contract in the off-season.
"I made the decision because I felt we were not progressing the way we wanted to progress," said general manager Ed Stefanski at a news conference. "I feel on the floor we weren't executing the philosophy that we want to have as Sixers basketball."
Stefanski said Tony DiLeo, the team's assistant general manager and senior vice president, will coach the team the rest of this season.
Excluding Brand's 15.9 points and 10 rebounds, the team's stars have not played up to past standards.
Andre Miller is averaging 15.5 points per game, Andre Iguodala 14.9 points, a drop of five points per game from last season, while Samuel Dalembert is down almost five points per game with his 5.8 points and just over two rebounds.
Cheeks compiled a 162-139 record in three-plus seasons and coached the 76ers to 40 regular-season victories in 2007-08 before a six-game loss to Detroit in the Eastern Conference quarterfinals.
He is the fifth NBA head coach fired this season, joining Oklahoma City's P.J.Carlesimo, Washington's Eddie Jordan, Toronto's Sam Mitchell and Minnesota's Randy Wittman.