Abstract: Objective: To determine the levels of IgG,IgA,IgM and C3,C4 in serum of patients with systemic scleroderma(SSc),and to investigate the relations between the immune indexes and SSc,and the significance of these indexes for clinical therapy as well.Methods: The above-mentioned immune markers were examined by scatter turbidimetry in 65 preliminarily diagnosed cases of SSc before and after treatment and 35 cases of healthy controls.And all the data were examined by t-test.Results: In SSc,the pre-therapeutic IgG and IgA were increased prominently;C3 and C4 were decreased;the variance had statistical significance compared with the health controls(P<0.01-P<0.001).Great differences were found in IgG,IgA,C3 and C4 in the 65 patients with SSc before and after therapy(P<0.05-P<0.001);IgM showed no change(P>0.05).Conclusions: The change of immune globulin and complement is closely correlated to the progress of SSc.Detection of their amount is helpful to both pathogenesis exploration and effect observation.