Located in the North Qilian orogenic belt, the Tongchanggou gold deposit is controlled by the tectonic altered zone and belongs to a small tectonic altered type high-grade gold deposit. Through field work, a mineralized alteration zone was discovered in the western mining area. Sample analysis along three sections shows obvious manifestations of mineralization and alterations, gold content in primary halo samples is the highest (0.2 ~ 4.5)×10^-6 and that in secondary halo soil samples is 0.1×10^-6, with silver also showing obvious abnormal display. Various chemically treated data all lie in the 3rd mineralized alteration zone with a turning point, indicating that the 3rd mineralized alteration zone is a geological body with certain extension. Through induced electric medium gradient method, it is found that the high polarization and low resistivity anomaly extends through the 3rd mineralized alteration zone. Geological, geochemical and geophysical data are consistent well with each other, which suggests that there still exists some prospecting potential, and future work should focus on the 3rd mineralized alteration zone.