The Zhibula copper polymetallic deposit is a typical skarn type deposit in eastern Gangdise metallogenic belt of Tibet, and garnet is the main skarn mineral in the ore district, with most metal minerals occurring between garnet grains. In this paper, such means as detailed borehole logging, rock-mineral identification under microscope and electron microprobe analysis were used to divide the zoning into two different types. There obviously exists vertical garnet zoning as follows: Garnet is mainly andradite in tuff comprising the roof, the garnet center is dark-colored and the color gradually becomes lighter towards the margin, accompanied by the change of the chemical composition from pure andradite to grossular. Garnet is mostly grossular near the marble floor, the color becomes dark from the center to the edge and the main chemical composition changes from andradite to grossular while other chemical components change quite insignificantly. These characteristics suggest that two distinct wall rocks made different contributions to the garnet formation. In the upper part, tuff mainly provided Fe composition, whereas at the bottom, marble contributed Ca ingredient, and hydrothermal fluids contributed Si, Al and some Fe. The rim of the garnet zone is different from the core because the environment and material compositions changed gradually during the whole process. This well explains the vertical garnet skarn zoning characterized by the change of the grossular in the upper part to andradite in the lower part. At the same time, the characteristics and zoning of the garnet show that Zhibula is a metasomatic hydrothermal deposit. The results obtained by the authors not only provide the basic data for the study of deposit genesis but also indicate the criteria in search for similar deposits in this region.