Objective To analyze the correlation between the thickness of the neck transparent layer (NT) measured by ultrasound and the chromosomal aberrations of the fetus, so as to provide evidence-based support for the early diagnosis and prevention of fetal congenital diseases. Methods A total of 106 pregnant women who admitted to Wuxi No.8 People’s Hospital from February 2018 to October 2020 were selected as the research subjects. All pregnant women were screened for fetal NT detection, and fetal chromosomal karyotypes were identified through prenatal diagnostic intervention methods. Calculated the proportion of fetal karyotype abnormalities and the NT value of fetal karyotype abnormalities, and analyzed the relationship between fetal karyotype abnormalities and NT thickness, maternal age, fetal abnormalities, fetal sex. Results? 106 pregnant women had undergone interventional prenatal diagnostic examinations and fetal karyotype analysis, among them, 19 fetuses (NT≥?3.0 mm) had abnormal chromosomal karyotypes, and the abnormal detection rate was 17.92% (19/106). The karyotype abnormalities included 2 cases of trisomy 13 (10.53%), 1 case of trisomy 18 (5.26%), 10 cases of trisomy 21 (52.63%), 1 case of 45, X (5.26%), 5 cases of 47, XXX (26.32%); as the thickness of NT increased, the rate of abnormal karyotype increased gradually; the thickness of NT in the normal karyotype group was lower than that in the abnormal karyotype group, and the age of childbirth was less than 35 years old, the proportion of fetal sex was male and the fetus without malformation were higher than that of the abnormal karyotype group (all P <0.05). Conclusion The pregnant women with pregnancy cycle between 11 weeks and 13+6 weeks, and the NT ≥?2.5 mm need to undergo fetal chromosome examination in order to further confirm the diagnosis and avoid the occurrence of neonatal dysplasia or defects.