Objective] To observe the alteration of specific IgG4 antibody of schistosomiasis patients before and after treatment. [Methods] ELISA. [Results] The SEA IgG4 and AWA IgG4 positive rates of 27 schistosomiasis cases were 96 3% and 100%, respectively,their average OD values were 1 62 and 0 72. 6 months post treatment 18 cases were followed up, the positive rates were 94 4% and 100%, respectively, their average OD values were 1 06 and 0 56, respectively. 12 months post treatment all cases were followed up, the positive rates of SEA IgG4 and AWA IgG4 were 96 3% and 92 6%, resepectively ,their average OD values were 0 99 and 0 58, respectively. [Conclusion] No obvious changes were found in the SEA IgG4 and AWA IgG4 positive rates of 27 schistosomiasis cases before and after treatment, whereas the antibody level of specific IgG4 was decreased.