The key to improve the efficiency of SSCL (solid state cathodoluminescence) is to improve the injection and acceleration of electrons in the accelerating layer. The electron acceleration ability of SiO is better than that of ZnS，while the latter is better than the former in the ability of injecting charges. So our attention was turned to the complex accelerating layer SiO2/ZnS，and prepared two kinds of devices to see whether the short peak occurrs. One of them is the low voltage mono-side recombination device, the othe the high voltage impacted two-side device. In result，under low voltage，the performance of the complex accelerating layer is superior to that of SiO2 and inferior to that of ZnS. Under high voltage，the complex accelerating layer is the best of all devices. Meanwhile，SiO2 was still found to be the main accelerating layer，yet ZnS is very useful for improving the performance in electron injection of SSCL device.