Ultraviolet imagers have been widely used in electric power and other fields. In order to accurately locate and detect defects and faults such as electric discharge, a scientific and reliable test platform and the corresponding test methods with unified core performance have been established. Firstly, the sensitivity measurement method for traditional ultraviolet imager high temperature blackbody is critically improved, and a new measurement method based on the standard solar-blind ultraviolet light source and collimator is proposed, in which the light source, integrating sphere and control system are used to achieve optical imaging test, UV sensitivity test and out-of-band suppression test. Finally, a new test platform for the optical imaging performance, ultraviolet sensitivity and out-of-band suppression performance of the ultraviolet imager is developed based on the new method. It is shown that the test method and the developed test platform proposed in this work can better evaluate the real performance of the ultraviolet imager and meet the actual test requirements of the ultraviolet imager.