The team said in a release Thursday night that "Fisher will no longer be the head coach of the team." The Titans announced the move within an hour of a report by SI.com that they were negotiating Fisher's departure.
The move comes only three weeks after owner Bud Adams announced Fisher would stay on for the final year of his current contract, a move that would have left Fisher coaching for his future.
The team also said a news conference will be held either later Thursday night or Friday to discuss the Titans' first coaching change since the franchise relocated to Tennessee from Houston in 1997.
A team spokesman did not immediately respond to messages from The Associated Press. Fisher did not answer a message left on his cell, and his agent also did not respond to messages from the AP.
The move caught most of the NFL by surprise.
Though Fisher had been derided locally as "Coach .500" or "Coacho Ocho," he seemingly had just survived a battle with quarterback Vince Young. Adams decided to either release Young or trade him on Jan. 5. The owner announced two days later that he would be keeping Fisher, leaving the coach to head into the 2011 season needing a playoff berth.
But Fisher didn't help himself when he fired his defensive coordinator Chuck Cecil a week ago after giving him a contract for the 2011 season.
Fisher has coached more NFL games for one franchise than all but six Hall of Famers: George Halas, Tom Landry, Don Shula, Chuck Noll, Curly Lambeau and Bud Grant. He ranks third among active coaches in career wins with a record of 147-126, behind only Bill Belichick (176) and Mike Shanahan (160), and he is 20th all-time in coaching victories.
Adams promoted Fisher from defensive coordinator to interim coach with six games left in the 1994 season after firing Jack Pardee. Adams removed the interim tag after that season and has stayed with Fisher longer than any other coach with the franchise the billionaire founded.
Fisher oversaw the team's relocation from Houston in which the Oilers played in four different stadiums between 1996 and 1999 before moving into their current home.
Since 1999, Tennessee ranks seventh in the NFL in winning percentage with a 110-82 record. The Titans also are tied for fourth with six playoff seasons since 1999, though a second straight miss this past season will drop the team down that list.
But the Titans haven't won a playoff game since beating Baltimore in a 2004 wild-card matchup. Tennessee lost a wild-card game in San Diego in 2007 and wasted the AFC's top seed in 2008.