A Catholic priest who pleaded guilty earlier this month to the sexual molestation of a young girl who was a member of his Gardner parish was sentenced yesterday to 5 to 7 years in the state prison in Walpole.

The Rev. Robert E. Kelley, 48, the former pastor of Sacred Heart Church in Gardner, pleaded guilty March 20 to charges of assault with intent to rape and two counts each of unnatural rape of a child and indecent assault and battery on a child. The offenses occurred between Sept. 1, 1983, and April 1, 1985, in Gardner.

Father Kelley was pastor of Sacred Heart in Gardner at the time, according to the Rev. John W. Barrett, director of communications for the Diocese of Worcester.

The female victim is now 16 years old. Her molestation came to light last year when she reported the incidents to a school official, according to Father Kelley's lawyer, Thomas F. McEvilly.

"I believe that you represent a continuing danger to young girls. The harm that you have caused cannot be measured," Superior Court Judge Herbert F. Travers Jr. said yesterday to Father Kelley before imposing the sentence. The 5- to 7-year sentence was recommended by Assistant District Attorney Mary Gecewicz. Father Kelley will be eligible to seek parole in three years and four months.

"The good things that you may have done, unfortunately, are of little consequence in light of these wrongs," Travers said.

The judge had earlier heard Father Kelley's tearful public apology to the victim and her family and testimony from psychiatrist Dr. Marc A. Whaley. Dr. Whaley said Father Kelley suffers from a psychiatric disorder known as "pedophilia," which he described as "a fixated interest in sexual activity with underage children."

In Father Kelley's case, Dr. Whaley said, the fixation involves "pre-pubescent girls." Dr. Whaley said Father Kelley's disorder was "unlikely to change or abate, especially by itself." He said the priest was in need of "many years" of psychotherapy and supervision that would prevent him from having contact with children outside of the presence of other adults.

Father Kelley told the court yesterday that he met the victim several years ago, at a time when he was "in very deep personal pain and confusion.

"I betrayed that sacred trust that she put in my hands," he said. "Though the words may ring empty, I express sincere sorrow. I'm sorry to her and I'm sorry to her family," Father Kelley said.

Bishop Timothy J. Harrington, of the Roman Catholic Diocese of Worcester, said the church and the community "share that family's pain."

"Today's sentencing of Father Kelley has completed the judicial phase of this painful reality. The process has been fair and just. Tremendous human distress lingers," the bishop said.

"I know that I am not alone in the depth of my concern for the victim and her loved ones," he said.

Father Kelley graduated from Assumption College and the University of Ottawa. He was ordained in 1968 and his first assignment as a priest was in June 1968 as an associate pastor at Notre Dame parish in Southbridge, according to Father Barrett.

In July 1974, he was assigned to St. Boniface Church in Lunenburg, where he served as associate pastor until November 1976, when he was transferred to St. Cecilia Church in Leominster, also as associate pastor, Father Barrett said. Father Kelley became pastor of Sacred Heart in Gardner in August 1983.

In April 1985, at the direction of his superiors, Father Kelley entered the House of Affirmation, a 14-month residential psychological treatment program in St. Louis, Mo., according to McEvilly. It was revealed in court yesterday that while undergoing therapy at the House of Affirmation, Father Kelley sent the victim in this case what Mrs. Gecewicz described as a "love letter."

Since 1985, Father Kelley has not been active in any ministry in the diocese, according to Father Barrett. McEvilly said yesterday he had been told by church officials that Father Kelley would not be assigned to any duties as a priest in the future. Father Kelley has been living with his parents in Worcester since 1986 and has been working as a still-life photographer and shrubbery and evergreen wholesaler, McEvilly said.

McEvilly recommended a sentence of 10 years at Concord State Prison. Under such a sentence, Father Kelley would have been eligible to seek parole in a year.

"What was taken from the victim in this matter, judge, can never be replaced," Mrs. Gecewicz said, reiterating her recommended sentence of 5 to 7 years. Mrs. Gecewicz said the victim and her family had been "devastated" and were in favor of "lengthy incarceration" for Father Kelley. Jane Adams contributed to this report.