ON BOARD THE USS NIAGARA FALLS IN THE PERSIAN GULF (AP) _ This supply ship that crew members affectionately call the K mart at sea is as close as U.S. Navy women come to combat.

Under U.S. law, women are barred from ships directly involved in fighting. Many of the 31 officers and enlisted women on the USS Niagara find the law frustrating, especially officers specializing in surface warfare operations.

It's the carriers, battleships and high-tech cruisers that attract all the glamour, the women note.

''It's ironic that the best ships they have opened to women are the last ships that men want,'' said Ensign Elizabeth Thomas, 23, of Chico, Calif., and a 1989 graduate of the Naval Academy.

The approximately 24 logistics ships were opened to women over the past three years. Previously, women were limited to tenders that hovered around ports and helped repair ships.

The logistics ships, which restock the fleet with fuel, ammunition and food, are deployed out of harm's way, but close enough to warships so the latter don't have to make port calls. This ship based in Guam sails in the lower Persian Gulf while doling out goods ranging from computer paper to 1.3 million eggs.

The crew was nervous entering the gulf on Jan. 16, just hours before the war started. That changed after the fighting started, although they still carry their gas masks everywhere.

''You look outside and you just see water. You don't see bombs going off or dead bodies floating by,'' said Janice Evans, a 28-year-old operations specialist from New Brighton, Pa.

The three aircraft carriers in the gulf have flown repeated strikes against Iraq and Kuwait. The battleships have launched scores of Tomahawk cruise missiles and other ships have skirmished with Iraqi ships. All the ships involved get their groceries and hardware from the USS Niagara Falls.

Women take part in all ship operations, from the boiler room to the guns. The ship has two 3-inch guns and .50-caliber machine guns for defense, but basically relies on the surrounding armada for protection.

''We are trained exactly like the men. ... We understand naval warfare,'' said Lt. Cmdr. Carol Rengstorff, 39, of Cresskill, N.J., and the ship's executive officer. ''Do we shoot Tomahawks? No. But there are other things to surface warfare.''

All the women came aboard over the past 13 months.

They said they faced hurdles in being accepted, especially with senior officers who have not worked with women, but feel they have become part of the team.

''They have a lot of trepidation, anxiety in working with women. They think it is going to be different,'' said Ms. Rengstorff.

The ship's doctor, Lt. Jean Nusbaum, 30, of Minneapolis, said all the men thought she was a nurse, and grumbled that the approximately 450-crew ship deserved a real doctor.

''There are still people afraid to come to medical because they don't want to see a woman doctor,'' she said. ''Some men wish they didn't have women on the ship. It changed the atmosphere. They think it was one big happy fraternity before the women came on board.''

Most men spoke favorably about having women. They said they can talk to them about difficult relationships, and men are taking better care of their uniforms.

Men and women from separate departments are allowed to date in port but not when the ship is at sea, although it is a difficult ban to enforce. The Niagara Falls, like other mixed ships, has had several cases referred to the captain for discipline.

The women officers said they avoid close working relationships with their male colleagues for fear it will taint their careers.

Women also said lack of opportunities to go to sea drive many from the Navy.

They dread the possibility that the logistics ship will be turned over to the Military Sealift Command, a civilian organization that operates some support ships. Such a change would sharply limit opportunities for a sea command.

Women officers hope the law banning them from combat ships will change within a decade.

''I understand it is a difficult thing to overcome the idea that someone's mother or someone's daughter might be fighting a war. I understand the emotion. But I don't think it should be any different from someone's son or someone's father fighting a war,'' Ms. Thomas said.