The invention relates to a plunger pump power end. The plunger pump power end comprises a machine body (1), a crankshaft (2) arranged in the machine body (1) and N transmission assemblies driven by the crankshaft (2) to permit radial-direction reciprocating motion. The N transmission assemblies are connected with N plungers (10) at the liquid force end respectively, wherein N is a natural number; the two ends of the crankshaft (2) are connected with the machine body through bearings; the plunger pump power end is characterized in that the N transmission assemblies are same in structure and all comprise connecting rods (3) and crossheads (4), wherein first ends of the connecting rods (3) are connected with a connecting rod shaft neck of the crankshaft through connecting-rod-large-end rolling bearings (8), the second ends of the connecting rods (3) are hinged to the first ends of the crossheads (4), the plungers (10) at the liquid force end are connected with the second ends of the crossheads (4). Compared with the prior art, the plunger pump power end has the advantages that the plungers at the liquid force end are directly connected with the crossheads, middle connecting rods are omitted, the problem that the middle rods are prone to oil leaking is solved, and assembling and disassembling are convenient.