NEW YORK (AP) _ Calling next week's ''Cagney & Lacey'' show ''a piece of pure political propaganda'' promoting abortion, the National Right to Life Committee is asking CBS to pull the episode about the bombing of an abortion clinic.

The Nov. 11 episode is ''unfair, unbalanced and shouldn't be broadcast on CBS,'' Dan Donehey, spokesmen for the National Right to Life Committee in Washington, said Monday.

The NRLC is sending a letter to Gene Jankowski, president of the CBS Broadcast Group, asking him to prevent the broadcast.

If that doesn't happen, the group is asking CBS stations to individually refrain from showing the episode entitled ''The Clinic.'' If stations broadcast the show, then the NRLC wants them to run as a follow-up the 30- minute program, ''Matter of Choice.''

Donehey said one CBS affiliate, WOW-TV in Omaha, Neb., already has agreed to carry ''Matter of Choice'' after next Monday's ''Cagney & Lacey'' episode.

If the local stations don't comply, Donehey said the NRLC, as a protest, is asking its supporters in local markets not to watch any CBS programs during the November sweeps, the period when ratings for local stations are measured and determine future advertising rates.

In response to the NRLC action, CBS, in a statement, said: ''CBS' program practices department has carefully reviewed this episode and feels it presents a balanced view of the issue.''

''Cagney & Lacey,'' which won an Emmy award as best dramatic series this year, is about a pair of female detectives who are partners on the New York City police force.

In ''The Clinic,'' Chris Cagney and Mary Beth Lacey investigate an abortion clinic bombing that killed a vagrant.

The NRLC also was upset that Barney Rosenzweig, the ''Cagney & Lacey'' executive producer, had pre-screened the episode to pro-choice groups, including the National Abortion Rights Action League and Voters for Choice, but not to pro-life groups.

A spokesman for CBS said that the network doesn't screen in advance programs for interest groups and that Rosenzweig did it entirely on his own.

Rosenzweig said at a press conference Monday that he gave pro-choice groups favored treatment to enlist their support and ward off the expected backlash from pro-life groups. The executive producer said a ''Cagney & Lacey'' episode in 1982 provoked ire from right-wing critics and, because of their protest, was not shown on several CBS stations, including Chicago.

Next Monday, ''The Clinic'' is up against NBC's well-publicized movie about AIDS, ''An Early Frost.''

Rosenzweig said he was in consultation with CBS executives when ''The Clinic'' was in the script stage and that there were no major disputes with the network. ''I feel we're presenting a balanced show,'' he said.

In the episode, Cagney (Sharon Gless) is confused about the abortion issue, while Lacey (Tyne Daly) reveals she had an abortion when she was 19 and unmarried. Both eventually advocate a woman's right to choose an abortion.

Rosenzweig said the anti-abortion position is expressed by a character played by Fionnula Flanagan. ''We made an effort to not make it a polemic and gave a lot of time to her statements,'' the producer said.

But Donehey said Flanagan's character came across as ''very strident and unfeeling. You didn't get any warmth or sincerity from her as a person. The only care and compassion came from the other side of the issue.''

Emily Tynes, a spokeswoman for the National Abortion Rights Action League in Washington, said ''the show is an accurate portrayal of violence against abortion clinics. We're very pleased that 'Cagney & Lacey' has chosen to deal with this issue. The public needs to be aware of the harassment that women are experiencing.''

Ms. Tynes said her group was giving a reception for ''Cagney & Lacey'' Tuesday on Capitol Hill.