To provide a plunger pump which can eliminate a seal material for preventing liquid leak and discharge a high viscous liquid, even not using a pump for forced-feeding.

A plunger pump is provided with a vessel 30 having a discharge port, a valve block 35 providing a slide surface 38, discharge port 41 and intake port 42, a pump block 50 supported rotatably in the vessel 30 under such state that the slide surface 51 is contacted with the slide surface 38 and having a plunger insertion hole 53 bored to a position communicated to the delivery port 41 and the intake port 42, a plunger 55 inserted to a plunger insertion hole 53 slidably, a coil spring 56 for energizing the pump block 50 to the valve block 35 side and a plunger advance/retreat drive means for advancing/ retreating the rotation drive means of the pump block 50 and the plunger 55.