Abstract: The tailing pond leakage in karst area is one of the main reasons which cause environment pollution by mining. Because the impact mechanisms are complex and the governance is difficult, it has become a major hidden danger in mining development. This work took the tailing pond of the Beishan lead-zinc mine as the research area. The formation and failure mechanisms of deep and shallow leakage were studied through investigating and analyzing the geological structure of tailings, karst development characteristic, engineering geologic conditions, hydrogeological conditions and other factors in the karst area. The results show that the main reason of tailing pond leakage is the bottom rock-soil mass penetrated by high voltage. The leakage areas are harnessed by bolt plugged technique，leak paths sealed by organic filling materials, groundwater diverted, slope surfaces protected, among other measures. After engineering treatment, it proves that the anti-seepage result of the leakage area is good.