Mike Ditka, who coached the Chicago Bears to the National Football League's best regular-season record (15-1), was named the league's coach of the year yesterday by the Associated Press.

Almost fired a year ago because of conflicts with team President Mike McCaskey, Ditka, 46, was an overwhelming winner in voting by sportswriters and broadcasters covering each of the NFL's 28 teams. He received 66 votes, with five going to runner-up Raymond Berry of New England and three to Dallas' Tom Landry.

Tom Flores of the Los Angeles Raiders, John Robinson of the Los Angeles Rams, Joe Gibbs of the Washington Redskins, Don Shula of the Miami Dolphins and Joe Walton of the New York Jets each received scattered support . . .

Mike Singletary, Walter Payton and Jim Covert were among six Chicago Bears named to United Press International's all-NFC team that also included Redskins receiver Art Monk and guard Russ Grimm.

Inside linebacker Singletary received 55 votes in balloting among 56 sportswriters, four from each NFC city. Running back Payton and tackle Covert tied for the lead among offensive players with 49 votes apiece. Center Jay Hilgenberg, defensive end Richard Dent and outside linebacker Otis Wilson were Chicago's other first-team picks.

Miami Dolphins quarterback Dan Marino, who held out early in the season because of a contract dispute, was named to UPI's all-AFC team for the third straight year.

Marino came back from a shaky start to lead the NFL with 336 pass completions in 567 attempts for 4,137 yards and 30 touchdowns. He received 23 votes in a close race with San Diego's Dan Fouts, who finished with 20 votes.

The West-champion Los Angeles Raiders placed four players on the team, including Marcus Allen, the only unanimous selection for the team.

The complete NFC team is listed on B6 . . .

Former Baltimore Colts quarterback Johnny Unitas wants his name and Hall of Fame-winning exploits stricken from the record and media books published by the Indianapolis Colts, saying he has been unable to identify with the team since its move from Baltimore in 1984.

"If they want to start out from the beginning, that's fine, but they have no right to anything that happened in Baltimore," Unitas told the Baltimore News American. "Records have never made any difference to me. Anyone who knows me realizes that. But I can't identify with Indianapolis. Nothing against Indianapolis, but I never played there."

"I would like for them to take my name out of their record book," he said . . .

Former Philadelphia Eagles Coach Marion Campbell said quarterback Ron Jaworski and tight end John Spagnola showed "a total lack of class" for saying Campbell was too easygoing with the National Football League squad . . .

Miami Dolphins Coach Don Shula will be the keynote speaker at the eighth annual Ed Block Memorial Courage Award sports banquet Feb. 18 at Martin's West near Baltimore. One member of each NFL team will receive an award for "courage exemplified in pursuit of professional excellence." Ken Huff is this year's Redskins recipient.