MANAGUA, Nicaragua (AP) _ The Defense Ministry said government forces killed 334 Contra rebels in 185 clashes last month.

The ministry, which released the figures Sunday, said 109 soldiers died in combat in January. It gave no figure for wounded troops, but said 104 Contras were wounded in the fighting.

The U.S.-backed rebels kidnapped 77 people, including women and children, ''in their desperate attempt to increase the number of their forces,'' according to the leftist government's communique.

The ministry reported that the U.S. Air Force, ''in support of its mercenaries,'' carried out five surveillance flights over Nicaraguan territory in January. The Nicaraguan government usually refers to the rebels as ''mercenaries.''

The communique added that ''all kinds of airplanes of the CIA, coming mostly from Honduras, violated (Nicaraguan) airspace 33 times'' in surveillance and supply flights.

The ministry reported Dec. 31 that 4,813 Contras were killed in combat in 1987, for an average of 401 per month. It gave no figure for December alone.