A convicted drug dealer who didn’t let being behind bars keep him out of trouble failed yesterday to get a new sentence under recent changes to the state’s Rockefeller drug laws.

Clarence Concepcion, serving 4½ to 9 years on a 2002 plea-bargained drug-sale conviction, was looking for a fixed term in the “low end” of the sentencing range, which would have made him eligible for immediate release.

But his prison disciplinary record defeated his bid for freedom.

Concepcion, who has already served 5½ years, has been slapped with six disciplinary infractions, including absconding from a work furlough and having gang insignia in his cell.

He was also thrown out of several programs, had to repeat anger-management training and lost his chance to have his sentence reduced for good behavior.

Queens Supreme Court Justice Joseph Grosso said he would have been inclined to grant Concepcion’s motion “had I seen more choirboy-type behavior during his incarceration.”