The United States will soon begin airlifting 2,000 members of a multinational peacekeeping force from Zaire's Shaba province, where they have been left virtually stranded since the United States flew them in to help quell a May 1978 invasion.

The Pentagon announced yesterday that the Air Force will use C141s to remove the troops, mostly Moroccans.

The troops were flown in to restore order in the Shaba region until French and Belgian troops could train the undisciplined Zairean army, which disintegrated into a mob of armed looters in the confusion following the invasion by Katangan rebels.

The administration's reluctance to remove the troops after more than a year reflected concern that the Zaireans were still unprepared to take over the peacekeeping function, according to State Department sources. The slowness in removing the force - which Morocco said so far had cost $15 million to sustain - had exacerbated already strained relations between the Carter administration and Morocco's King Hassan.

House and Senate conferees last month authorized the funds to airlift the peacekeeping force out of Shaba. Said Rep. Stephen Solarz (D-N.Y.), "I can't think of anything more unconscionable than to give anyone a one-way ticket to Lubumbashi," a city in the province.