Abstract: Manual grease gun comprising a tubular reservoir (1) for the grease (7) closed by a rear cover (3), a dual seal pressure piston (10) slidable within the container (1) and a head piece (2) with a reciprocating piston (5) pump manually operated through a lever (6), the suction port of the pump being connected with the interior of said tubular reservoir (1) and the delivery port of the pump being connected with a grease delivery nozzle (8); on the rear cover (3) or on the rear region of the tubular reservoir (1) there is provided a manual reciprocating air compressor (4), the delivery port of which is connected with a rear pressure chamber (12) of the tubular reservoir (1). The diameter of the reciprocating compressor (4) is smaller than the diameter of the tubular reservoir (1), the ratio being preferably below 1/4.