The invention discloses a dynamic load bearing design method applied to a reciprocating compressor crankshaft. The method solves the problems that in the traditional dynamic load bearing design process, parameters are difficult to determine, and characteristic parameter calculation is complex. The design method comprises the steps of width-diameter ratio design and radius gap interval computationin the bearing design process, and further comprises the step of calculation of pressure distribution, minimum oil film thickness, oil film pressure, lubricating oil flow, power loses, equivalent temperature rise and the like of a bearing, all parameter indexes of the bearing are checked more comprehensively, and the design objective safety is high. According to the method, a finite element methodis adopted for solving a Reynolds equation, compared with traditional experience formula computing, more parameters can be obtained, as for the bearing, with the complex variable working condition, like the dynamic load bearing, the design steps are simplified, and the design time is saved; and design of a bearing oil inlet hole is carried out by drawing a cloud picture of a pressure crankshaft angle and a bearing circumferential unfolding angle.