Abstract: Objective To explore further the long-term effects on human immune function of arsenic exposure caused by burning coal,and to provide scientific evidences for prevention and intervention of arsenism.Methods Variation conditions of peripheral blood T-lymphocyte subsets Cd3⁺ ,CD4⁺ and CD8⁺ cells were measured with alkaline phosphatase-anti-alkaline phosphatase bridged enzyme linked immunosorbent assay(APAAP),and analyse the changes of T-lymphocyte subsets before and after 7 years.The contents of serum immunoglobulin IgG,IgM and IgA,and complement C3,C4 were detected with immune turbidimertry.Results The content of IgG in arsenism patiens was significantly higher than the control group,while the level of C4,C3⁺,CD4⁺ and CD4⁺/CD8⁺ were significantly decreased compared with control group(P<0.05).The differences of other indexes did nothave significance in statistic.The levels of T-lymphocyte subsets didn't show evident changes before and after 7 years(P<0.05).Conclusion The changes of human immunoglobulin and complement,and persistent of T-lymphocyte subsets might not only be a cause of arsenism,but also be related with the continual developing condition of arsenism.Taking some pointed measures to enhance immunological function may be helpful for the prevention and intervention of arsenism.