The exploitation of mineral resources has caused serious soil heavy metal contamination in China, especially at metal mine sites and the downstream areas. However, there were few studies assessing the nationwide soil heavy metal contamination risks induced by mining activities, as well as the major drivers in influencing metal availabilities. We have collected 420 soil samples from 58 metal mine areas across China and evaluated total and available soil heavy metals and other soil properties. The geo-accumulation index, potential ecological risk index, and availability ratios were applied to assess the potential heavy metal risks levels. The results showed that soil from lead-zinc mines had the highest pollution level, followed by soil from copper mines and iron mines. Geologically, the pollution risks were higher in southern China especially for Cd. A series of multivariate analysis were carried out to evaluate the environmental drivers regulating metal availabilities on a national scale. Soil physicochemical property is identified as the major factor relating to metal availability. Among all detected soil factors, heavy metal availability was significantly affected by soil pH, and followed by electrical conductivity and total S content. In sequential equation modeling, geographical category of annual temperature and precipitation could influence the soil heavy metal availability by influencing soil category of pH and EC. We provide a comprehensive assessment of soil heavy metal pollution risks derived from mines in China while identifying major factors in influencing heavy metal availabilities on a national scale.