Objective To investigate the effect of fetal hemoglobin( HbF) in improving anemia of women who were β‐thalasse‐mia carriers at childbearing age .Methods 289 cases of women at childbearing age diagnosed as β‐thalassemia carriers in Shenzhen City were enrolled in this study .The high performance liquid chromatography (HPLC) was uesed for quantitative analysis of HbF , and the red blood cell parameters were detected by using the LH750 Automatic blood cell analyzer .The differences of red blood cell parameters between the HbF normal group and the HbF increased group were compared ,and the relationship between the high HbF expression rates and gene mutations were also analyzed .Results Comapred with the HbF normal group ,the hemoglobin (HGB) levels ,mean corpuscular volume (MCV) and the mean corpuscular hemoglobin (MCH) increased significantly ,while the red blood cell (RBC) count reduced ,there were significant differences between the two groups (P<0 .05) .No significant differ‐ences of the mean corpuscular hemoglobin concentration (MCHC) and RDW coefficient of variation (RDW‐CV) between the two groups were found(P>0 .05) .There were no significant differnces of rates of HBF high expression between different types of β‐globin gene mutations and the overall rate of HBF high expression (P>0 .05) .Conclusion Compared with the HbF normal group , anemia may improve more significantly in cases of women diagnosed as β‐thalassemia carriers at childbearing age in the HbF in‐creased group ,and there may be no relationship between gene mutations and high expression of HbF .