The move comes after a 3-8 season which saw the Bearcats win their last two games.
Allen just completed his sixth season and is 27-39 overall.
When he took over the program, SBU dropped out of the MIAA in football and Allen helped rebuild the program. He had three winning seasons before 2012.
The Bearcats are transitioning back into MIAA play.
SBU Athletics Director Mike Pitts thanked Allen for laying the foundation for the next coach.
Allen who also was an assistant coach at SBU for two years was stunned.
"It was most definitely shock," says Allen. "There was not inclination throughout the course of the season that they were looking to make a change. There will obviously be some challenges in the MIAA. Because the MIAA is a football first conference and this is a basketball first school. I mean they make that well known. I thought that we competed well. And played hard. As a coach you want to win them all. And when you don't there's something you have to fix. But did your players compete? I thought we did."
SPRINGFIELD, Mo. -- Monday Missouri State safety Caleb Schaffitzel was named third team All-American from The Sports Network.
Tuesday offensive right tackle Randy Richards was named All-American from the American Football Coaches Association.
Richards is a Juco transfer from West Palm Beach, Florida and was named the Bears' offensive lineman of the year and earned second team All-Valley honors.
The Missouri State co-captain said the 3-8 season was a disappointment but he's thrilled with the honor.
"I kind of wanted to come in and do my best to help the team win," said All-American Randy Richards. "We didn't really achieve the goals that we wanted to achieve as a team. But by me working as hard as a I could every single day. Taking the coaching and being a leader, I felt that I earned this award. I'm very humbled by the experience and thankful."
POINT LOOKOUT, Mo--Evangel and College of the Ozarks renewed their Highway 65 rivalry Tuesday night.
Back on November 5th Evangel beat the Bobcats by four points in Springfield.
Tuesday night it was at the Keeter gym, the last time Evangel beat C of O in Point Lookout was in 2004.
And the Bobcats taking it inside early, nice look to Nate Simniok off the glass 4-nothing C of O.
Later the 'Cats on the break, Dami Sapara to Ethan Murray back to Sapara, but he misses the ally-oop, but Mike Wiebe is there for the follow up board and basket, 8-3 C of O.
Evangel taking it down low to Stephen Cotton, he's working hard on the low block, and the jump hook goes in, it's a two point game.
C of O with a little inside, out action, to Simniock who hits the three from the top of the key, 12-8 Bobcats.
Evangel trying to keep pace, Josh Veurink with the scoop shot and the foul, 14-10.
But College of the Ozarks would get its revenge on its home court, Wiebe with the three, he finished with 27, Simniock had 26 and the Bobcats win 80-67.
SPRINGFIELD, MO--Boys high school basketball Tuesday night, Nixa paying a visit to Glendale.
And a well dressed crowd on hand.
Glendale would jump in front early in the first, Remington Barbo with the three pointer from the top of the arc, it's 6-2 Falcons.
But Nixa would answer with senior sharp shooter Austin Ruder, he swishes the catch and shoot three, it's a one point game.
Glendale not afraid to take it inside, nice pass from Nate Nagy to Cameron Maes with the hoop, it's 10-7 Falcons.
Nixa would pull away in the second quarter, Ruder with the three pointer, and the Eagles run away with it late 77-47.