An electron-bombarded active pixel sensor (EBAPS) is a type of vacuum-solid hybrid low light-level device that encapsulates a photocathode, an electronic-sensitive active pixel sensor (APS) chip, and a base, using vacuum technology. Integral sensitivity is a crucial performance parameter of EBAPS, but corresponding test methods in China are lacking. Therefore, based on the working principle of EBAPS and the spectral response test method of a low-light level-image intensifier, the spectral responsivity is characterized by a digital-electron conversion factor and the number of electrons obtained from the output signal in this study. Moreover, a spectral response test system of EBAPS is designed. The spectral response curves of EBAPS at an operating voltage of -800 V are obtained using this system. The EBAPS’ integral sensitivity is 3.2 × 10⁸ (s·lm)^-1, and repeatability is 0.65%.