Abstract： Objective To explore the application value of combining chromosome microarray and chromosome karyotype analysis in prenatal diagnosis of fetal ultrasound abnormalities.Methods 547 pregnant women with fetal abnormalities detected by ultrasound in our hospital from January 2018 to December 2023 were collected,and amniocentesis was performed for chromosome karyotype and chromosome microarray(CMA)analysis.Results 547 fetal chromosomal karyotypes and CM A were successfully detected,with 27 cases showing abnormal chromosomal karyotype results and a detection rate of 4.9％(27/547);59 cases had abnormal CMA results,with a detection rate of 10.8％(59/547),including 36 cases of pathogenic CNVs,2 cases were potentially pathogenic CNVs,and 21 cases of CNVs with unknown significance.There were 21 cases with abnormal and consistent chromosomal karyotype and CMA detection results,19 cases of chromosomal number abnormalities and 2 cases of chromosomal structural abnormalities.There was 1 case with abnormal and inconsistent results,which was a marker chromosome.There were 8 cases of chromosomal karyotype abnormalities with normal CMA results,and chromosomal karyotype abnormalities were mainly structural rearrangement abnormalities.There were 37 cases of abnormal chromosomal karyotypes and abnormal CMA results in ultrasound fetuses.Conclusion Chromosomal karyotype analysis combined with CMA technology can further improve the detection and accuracy of chromosomal abnormalities in ultrasound fetuses,exhibiting the complementary relationship between the two methodologies..For fetuses with ultrasound abnormalities,it is recommended to offer both karyotype analysis and CMA technology simultaneously.