OBJECTIVE To investigate the effect of Yisui Shengxue Granule (, YSSXG), a complex Chinese medicine, on the oxidative damage of erythrocytes from patients with hemoglobin H (HbH) disease. METHODS Twenty-two patients with HbH disease and 22 healthy volunteers were observed. YSSXG was given to patients with HbH disease for 3 months. Before and after the 3-month treatment, blood parameters [hemoglobin (Hb), red blood cells (RBCs), and reticulocyte percent (Ret)] were examined; inclusion bodies in erythrocytes were observed by transmission electron microscopy (TEM); activities of antioxidant defense enzymes [superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (Cat)] and erythrocyte membrane malondialdehyde (MDA) concentrations were determined. RESULTS In patients with HbH disease, measured values of RBC and Hb obtained from the first to the third months after treatment with YSSXG were significantly higher than before treatment (P<0.01). Measured values of Ret from the second to the third months after treatment were significantly lower than before treatment (P<0.05 and P<0.01, respectively). Prior to treatment with YSSXG, TEM images of RBCs showed the presence of numerous inclusion bodies. After treatment with YSSXG, the amount and volume of inclusion bodies decreased. Treatment with YSSXG also led to a significant increase in SOD activity (P<0.01), a decrease in Cat activity (P<0.01), and no significant differences in GSHPx activity (P>0.05) or MDA concentration (P>0.05). However, compared with the healthy counterparts, SOD, GSH-Px, and Cat activities presented at high levels (P<0.01) both before and after treatment. CONCLUSIONS YSSXG could improve the degree of hemolysis and anemia in patients with HbH disease. The mechanism may be related to its antioxidative effects, which could elevate the activity of total SOD in erythrocytes and efficiently inhibit the oxidative precipitation of β-globin chains.