〔Abstract〕 Objective To establish normal range of fetal anterior-posterior diameter, left-right diameter, and endometrium to lay the foundation for finding abnormal uterine development and diagnosing bisexual malformations. Methods The study subjects were 213 pregnant women with a gestational age of 21～41 weeks. Ultrasound was used to measure the anterior-posterior diameter, left-right diameter, and endometrium of the fetus.And analyzed the correlation between uterine development and gestational age. Results Sufficient measurements were obtained in 213 cases of fetal uterus examination. In the range of 21～34 gestational weeks,the relationship between fetal anterior-posterior diameter, left-right diameter, endometrium and gestational week was expressed by regression equation:anterior-posterior diameter(mm)=1.240×gestational weeks(r=0.887,P<0.0001)-23.969, left-right diameter(mm)=1.579×gestational weeks(r=0.915,P<0.001)-30.968,endometrium(mm)=0.802×gestational weeks(r=0.892,P<0.001)-16.585. Between the range of 35～41 gestational weeks,the 95% confidence interval of the population mean was calculated by usingtdistribution method:anterior-posterior diameter(15.992, 17.092) mm、left-right diameter(20.478, 21.627) mm、endometrium(8.805, 9.910) mm. There was a linear relationship between fetal anterior-posterior diameter, left-right diameter and endometrium. Conclusions The anterior-posterior diameter, left-right diameter and endometrium of the uterus increased with the increase of gestational age before 34 weeks, reached the slow growth stage to the plateau stage after 34 weeks, and no longer increased significantly with the increase of gestational age.