CHATTANOOGA, Tenn. (AP) _ An attorney who pleaded guilty to helping a penitentiary inmate escape and who spent five months with him on the run was released today after serving more than 10 months in prison.

Mary Evans, 28, was discharged about 8:40 a.m. EST from the state work release center in Chattanooga, where she had been housed since mid-November, said Warden John Patterson.

''Her parents picked her up,'' Patterson said. ''She's going to go home to Knoxville, I'm assuming, and then report to her parole officer.''

Ms. Evans, who will be on parole until her three-year sentence expires in 1987, was scheduled to take a clerical job with Kimberlin Heights Industries Inc., a Knoxville tube manufacturing firm.

''I think she wants to go back into society and proceed with her normal lifestyle, as much as one can expect with her notoriety,'' Patterson said.

Ms. Evans was disbarred after pleading guilty in March 1984 to slipping a gun to client William Timothy Kirk and helping him overpower three guards and flee from an Oak Ridge psychologist's office on March 31, 1983.

At the time of the escape, Kirk was serving 65 years for armed robbery and awaiting trial in connection with a shootout that killed two Brushy Mountain State Penitentiary prisoners.

Ms. Evans and Kirk remained at large for 139 days before FBI agents captured them in August 1983 at Daytona Beach, Fla.

Prosecutors agreed to recommend probation for Ms. Evans, but Anderson County Criminal Court Justice James B. Scott sentenced her to three years after she refused to take the witness stand and apologize for her actions.

Ms. Evans won parole Oct. 10, and was transferred from the Tennessee Prison for Women to the work release center a month later because of good behavior.

At the work release center, Ms. Evans spent two weeks doing clerical work for Chattanooga attorney Jerry Summers before questions about the ethical propriety of that employment prompted her to quit. For the last month, she had worked at Erlanger Medical Center in Chattanooga.