To explore the value of non-invasive embryo chromosome screening (NICS) in improving the outcomes of clinical pregnancy after assisted reproduction in men with severe oligo-astheno-teratozoospermia (OAT). METHODS We randomly selected 170 cases of assisted reproduction due to severe OAT from January 2017 to December 2020, 85 undergoing NICS treatmentand the other 85 receiving intracytoplasmic sperm injection (ICSI). We made comparisons between the two groups in the female age, body mass index (BMI), anti-Müllerian hormone level (AMH), basal antral follicle count (AFC), infertility duration, male age, sperm concentration, percentages of progressively motile sperm (PMS) and morphologically normal sperm (MNS), sperm DNA fragmentation index (DFI), numbers of oocytes retrieved and high-quality blastocysts, and rates of normal fertilization, clinical pregnancy and abortion. RESULTS No statistically significant differences were observed between the two groups in the female age, female BMI, AMH, AFC, infertility duration, male age, sperm concentration, percentages of PMS and MNS, sperm DFI, numbers of oocytes retrieved and high-quality blastocysts, or normal fertilization rate (P > 0.05). The rate of definite diagnosis was 88.24%, and that of embryo chromosome euploidy was 48.56% in the NICS group. The rate of clinical pregnancy after selected euploid embryo transfer was significantly higher in the NICS than in the ICSI group (66.28% vs 51.09%, P < 0.05), while that of abortion remarkably lower in the former than in the latter (12.28% vs 29.79%, P < 0.05). CONCLUSIONS For male infertility patients with severe OAT, NICS technology can improve the rate of clinical pregnancy and reduce the risk of abortion.