The invention discloses an engine and hydraulic element power matching testing method and system. The method includes the steps of collecting characteristic parameter values of an engine and characteristic parameter values of a hydraulic element, obtaining actual output torque and actual output power of the engine according to the characteristic parameter values of the engine, forming the actual torque characteristic curve and the actual universal characteristic curve of the engine according to the actual output torque and the actual output power respectively, obtaining torque of the hydraulic element according to the characteristic parameter values and actual output torque of the hydraulic element, obtaining matched torque, meeting a preset matching condition, of the hydraulic element according to the torque and the actual torque characteristic curve of the hydraulic element, obtaining power corresponding to the matched torque, generating a power spectrum on the actual universal characteristic curve, and evaluating power matching according to the power spectrum and the actual universal characteristic curve. Through the method, reference data are provided for the design and the improvement of a hydraulic transmission machine, and the improvement to performance of the engine and performance of the hydraulic element is facilitated.