CHICAGO (AP) _ A Roman Catholic parish plans to offer special services to anoint AIDS victims, hoping to promote psychological and spiritual healing.

The sacrament, called ''Anointing of the Sick,'' was previously called extreme unction or last rites and was reserved for those about to die, Sister Joy Clough, a spokeswoman for the Archdiocese of Chicago, said today.

It was changed by the Second Vatican Council to cover those who have a serious illness or who are very old and feel a need for spiritual strengthening, she said. A person can receive the sacrament more than once and it can be given in a communal setting.

''These are Catholic people who are very sick,'' said Paul Spalla, a deacon at Our Lady of Mount Carmel Catholic Church, which has scheduled the first group anointing for AIDS victims later this month. ''The reason for doing this is for healing hurts and comforting.

''This is an experiment to reach parishes where there is a big number of people with the disease,'' he said.

If the services are successful at Mount Carmel, said Spalla, they will be rotated among that North Side church and four other parishes.

The plans come at a time of tension between homosexual groups and the Chicago Archdiocese, and some activists were critical.

''Why are they waiting until people are dying to do that?'' asked Paul Varnell, director of research for the Illinois Gay and Lesbian Task Force. ''It would be more appropriate for people with AIDS to anoint the hierarchy of the Catholic Church, which is the one in need of forgiveness.''

Jim Bussen, national president of Dignity, an organization of homosexual Catholics, said he doubted whether the anointing service would affect the church's stand on homosexuality, which officially has been declared a sin.

But Bussen said his group was pleased that the parishes were taking a lead in ministering to AIDS victims.

''It shows that AIDS care starts at the grass-roots level,'' he said.

Spalla said the service would include scripture readings, prayers and singing, and would last no longer than 45 minutes.

''These are very sick people so it can't be long,'' he said.

AIDS, short for acquired immune deficiency syndrome, destroys the body's immune system and leaves it vulnerable to a variety of other deadly ailments. Spread by sexual contact, shared hypodermic syringes and blood transfusions, AIDS is fatal. More than 21,000 victims have died in the United States.