The California Board of Prison Terms today paroled Isa Mae Lang, but she has no desire to move after 47 years and is waging a desperate battle to spend the rest of her life behind bars. At 93, she is believed to be the oldest female inmate in the United States.

Lang was convicted in 1935 of murdering her landlady. Incarcerated in the California Institute for Women in Frontera, about 45 miles east of here, she has made a comfortable life for herself in her cell, and doctors say the stimulation she gets from the younger prisoners may have helped keep her alive. She keeps busy folding laundry in the prison infirmary.

But California prisons are overcrowded, and the prison panel ruled that she must be released to a convalescent home for the elderly early next year.

"It's inappropriate and unnecessary to remove her from the stable and warm living environment she is in," said Los Angeles County Deputy District Attorney Charles Havens, who was in rare agreement with Lang's attorney that she should be allowed to stay.

But a spokesman for the prison board said space has become precious at Frontera, as well as in prisons throughout the country.

Lang has her own room, with comfortable furniture and bright decorations, which she spends much time keeping neat. But single quarters are an increasingly rare luxury for prisoners in California, where there are 33,000 state inmates but facilities built for 25,600. State corrections department assistant director Philip Guthrie said the situation is so bad the state plans to begin housing some prisoners in tents next spring.

During today's hearing, board members expressed sympathy for Lang but said that, despite her life sentence, she met their criteria for release -- no prior record, model behavior in prison and a low likelihood of committing further crime. Lang's attorney indicated he was studying a possible appeal of the board's decision to force her release.

Prison associate superintendent Dennis Martel said Lang was "well-liked by everyone who comes in contact with her. She's kind of a folklore figure here."

Lang has avoided publicity, once saying she did not want to be "plagued by do-gooders trying to get me out of this place." She declined to attend today's hearing when she learned that a reporter for the Los Angeles Times would be present, but told board members at an earlier hearing:

"Everyone is good to me here. The only care I have to have from the aides is to help me in and out of bed and to clean the floor. I bathe myself. I dress myself. I make my bed. They never have to touch it."

Born an illegitimate child, Lang told the board she shot the landlady to death at her Los Angeles boarding house 47 years ago "because she called me a bastard and a harlot." Now thin and frail, moving around most of the time in a wheelchair, Lang has twice tried to adjust to life on the outside, briefly in the 1940s and then for a longer period from 1960 to 1969, when a technical parole violation landed her back in Frontera.

Of that second, temporary parole, she earlier told the board, "The first five years, I really enjoyed. I had my own little room and a beautiful little cat named Ginger. But the last four years were hell. I became sick. I had to give up my apartment and put my cat to sleep.

"I went into a nursing home, where I shared a room with five women who were all senile. It was terrible. I was so lonely for all my friends back in prison. And I knew if I went back I'd have a room of my own."