By the methods of field sampling and indoor incubation, this paper studied the accumulation and mineralization of soil organic matter under impact of heavy metals pollution. The results showed that high amount of heavy metals in polluted soil could slow down the mineralization rate of soil organic C, and increase the amount of hardly biodegradable organic C. With increasing soil heavy metals pollution, the particulate organic matter and its proportion in total soil organic C increased, while the microbial biomass C and its proportion in total organic C decreased. Heavy metals were largely enriched in particulate organic matter, which could impact the further mineralization of soil organic matter. In a word, soil heave metals pollution could change the mineralization rate of soil organic matter, and affect its accumulation and distribution.