Abstract: Pot experiments were conducted to study the accumulation behaviors of mercury (Hg) in different mature rice tissues grown in the paddy soil from South Jiangsu Province, which was treated with exogenous inorganic Hg and rice straw incorporation. In addition, the impact factors of Hg accumulation in the rice grain were analyzed. The results show that exogenous Hg in soils significantly inhibited the growth of rice, with significant decrease in rice root and shoot biomass, as well as rice yield. The average rice root, shoot biomass, and rice yield were decreased by 35%, 24%, and 35%, respectively. The content of Hg in rice grain grown in the pot soil same as the field soil was lower than that of rice grain grown in the field soil, indicating that the Hg sources of rice in the paddy field were diverse, and the impacts of difference between the pot experiment and the field system also existed. The enrichment of Hg in mature rice tissues was increased obviously under the conditions of pot soils treated with exogenous Hg, and the average Hg content of rice grain, rice husk and straw were increased by 220.9, 39.5 and 97.8 μg·kg^-1, respectively. In different pot soil, the impact of rice straw incorporation on the migration of exogenous Hg to various tissues of rice was distinct. Soil pH, cation exchange capacity (CEC), organic matter (OM) and calcium carbonate can affect the accumulation of Hg in rice grown in soils treated with exogenous Hg. The ability of rice grain to enrich Hg was stronger than that of rice hull. The increasing rate of rice grain enrichment ability to Hg was higher than that of rice straw under the conditions of the experimental soil treated with exogenous Hg.