Au photocathode is used in photon counting imaging system with induction readout. A 15 nm gold film is deposited on the resolution test board and it is used for transmission photocathode. The gain performance of micro-channel plates (MCP), resolution and counting rate of the detector with Au photocathode are tested. The results show that the system with Au cathode has a quasi-Gaussian pulse height distribution (PHD) curves. The peak of the PHD curves moved to the high-gain zone and the full width at half maximum (FWHM) gradually widened as the voltage increased. After the adoption of Au cathode, the detection efficiency and the signal-to-noise ratio of photon counting imaging detector effectively improved. The resolution test results show that the spatial resolution of the detector is better than 75 μm, and the counting rate can reach 13.5 kHz when the system′s resolution is better than 150 μm.