The invention belongs to the technical field of medical biomaterial property test, and particularly relates to a biomechanical property testing device and a testing method for blood vessel prosthesis. The testing device includes a liquid storage box, a current guide silicon tube, an electronic peristaltic pump, a current limit switch, a conducting wire, a computer mounted with signal processing and converting software and data output equipment as well as a sample fixing device, a pressure testing device and a displacement testing device. By utilizing the device, the relation curve of the pressure and the tube diameter is measured and recorded in real time, so that the detecting results of compliance, fatigue resistance and bursting pressure are calculated and obtained, and the biomechanical properties of the blood vessel prosthesis are scientifically tested and evaluated; therefore, the technical problem of testing the biomechanical properties of the integral blood vessel prosthesis under the existing physiological status is solved, the integral testing and evaluation of the compliance, the fatigue resistance and the bursting pressure of the blood vessel prosthesis are realized, and scientific and reliable evidences are provided for choosing the blood vessel prosthesis with the biomechanical properties meeting the requirements.