Abstract: Objective To investigate the clinical value of gnome-wide chromosome microarray (CMA) technique in genetic etiological diagnosis of fetal cerebral ventriculomegaly. Methods A retrospective analysis was conducted in 109 women with singleton pregnancy, who were admitted in Nanfang Hospital with the diagnosis of cerebral ventriculomegaly in the fetuses by ultrasound between January, 2014 and December, 2016. Routine karyotype analysis and chromosome microarray analysis were performed to identify the chromosomal abnormalities in the fetuses. Results Karyotype analysis detected chromosomal abnormalities at a rate of 12.84% in these fetuses, significantly lower than the rate of 26.60% with CMA technique (P=0.004); the combined detection rate of the two techniques was 28.44%. In 17 cases, karyotype analysis yielded normal results while CMA microarray showed abnormalities with an extra abnormal detection rate of 15.60%. Among the 17 fetuses with chromosomal abnormalities, 6 had micro-deletion, 9 had micro-duplication, 1 had both micro-deletion and micro-duplication, and 1 had heterozygous loss of single parent diploid. Conclusion CMA technique can be used to detect abnormal chromosomal copy numbers in fetuses with cerebral ventriculomegaly to increase the detection rate of chromosomal abnormalities and facilitate prenatal consultation and prognostic evaluation.