To assess the value of chromosomal microarray analysis (CMA) for the analysis of 824 samples from miscarriage or stillbirth.Copy number variations (CNVs) in the abortic chorionic villi or stillbirth tissues were detected by CMA.All specimens were successfully analyzed, among which 381 (46.2%) were diagnosed with chromosomal abnormalities, which included 312 (81.9%) numerical abnormalities, 66 (17.3%) structural abnormalities and 3 (0.8%) uniparental disomies. Among numerical chromosomal abnormalities, aneuploidies was most common (92.0%), with trisomy 16 and 45,X accounting for 41 (13.1%) and 63 (20.2%) of the cases, respectively. Among the 66 structural chromosomal aberrations, there were 26 (39.4%) CNVs duplications, 20 (30.3%) CNVs deletions, and 20 (30.3%) CNVs duplication and deletions. 33 CNVs were predicted as have a high chance to lead to a disease.CMA is a reliable, robust, and high-resolution method for the analysis of miscarriage or stillbirth samples. Numerical aberrations, in particular chromosomal aneuploides, are the main cause for spontaneous abortions and stillbirths.