individual mineral particulates in PM10 samples, collected over different months in Beijing, were analyzed by SEM/EDX. The results show that mineral particulates in PM 10 over Beijing are complex and heterogeneous. Some 38 mineral species in PM10 were identified, in which clay minerals occupy the dominant position, accounting for 30.1%. The illite/smectite mixed layers seem to be the most common species in clay minerals. Quartz, calcite, composite particles and carbonaceous particles make up 13.5%, 10.9%, 11.95% and 10.31% respectively. Gypsum, feldspar and dolomite are below 10% on average. Fluorite, apatite, halite, barite and zinc chlorides were recognized firstly in Beijing PM10 . Sulfuration occurs on the surface of most mineral particles, especially in summer, suggesting a relatively extensive atmospheric reaction over Beijing in summer.