To investigate the effects of Virgate Wormwood Decoction on ABO blood group incompatibility titer and immune function in pregnant women.Methods:During 2014 January to December 2014,total 128 cases of pregnant women diagnosed as ABO blood group incompatibility included in the study were randomly divided into observation group and control group by random number table,64 cases in each group.Two groups were given routine symptomatic processing,additionally the control group were treated with Yin Zhi Huang oral liquid while the observation group given modified Virgate Wormwood Decoction for treatment and pregnancy period of treatment of two groups were 30 days.The antibody titer,and the immune function,and the treatment effect were compared between the two groups.Results:As for the clinical efficacy:in observation group,the total efficiency was 95.31%,which was significantly higher than that of the control group’s 82.81% (χ2=5.133,P<005); as for the serum antibody level:in the observation group,the level of serum antibody in 1:64 and below 87.50%,which was significantly higher than that of control group’s 5000% (χ2=19.236,P<005); immune function:CD3+,CD8+ of the observation group were higher than that of the control group,CD4+ counts,the ratio of CD4+/CD8+ were lower than control group (P<005,t＝2.308~11.158).Conclusion:Virgate Wormwood Decoction with syndrome differentiation is beneficial in reducing ABO blood group incompatibility of maternal antibody titer,improving maternal immune function as well as the therapeutic effect.