The invention provides a battery assembly service life testing method. According to the battery assembly service life testing method, discharging capacity attenuation amplitude which corresponds with each battery assembly is calculated through a testing service according to a battery parameter of the battery assembly, and furthermore a corresponding service life period of the corresponding battery assembly is determined according to the calculated discharging capacity attenuation amplitude. The method provided by the invention has advantages of realizing accurate centralized service life prediction to a battery and a battery pack which are diversely used, effectively preventing battery service life monitoring effectiveness reduction caused by historical battery parameter lost of the battery assembly, ensuring high service life calculation accuracy of the battery assembly, greatly reducing calculation amount in calculating the service life of the battery assembly, effectively reducing cost of the battery assembly, and effectively improving operation efficiency in calculating the service life of the battery assembly.