Background; Abdominal wall defects (AWDs) define as a type of congenital anomalies characterized by the herniation of abdominal organs through an unusual opening surrounding the umbilical cord. The most common two types include omphalocele and gastroschisis. Omphalocele is an opening in the center of the abdominal wall where the umbilical cord meets the abdomen. Gastroschisis is a defect in the abdominal wall, usually to the right of the umbilical cord. Both have reported incidences around 1 in 4,000 live births. Objective: To determine the magnitude of major abdominal wall defects among new born admitted to NICU of HUCSH and to identify associated risk factors of major abdominal wall defects among new born admitted to NICU of HUCSH at Sidama Region, Ethiopia, 2021. Methods: A facility based cross-sectional study was conducted in Hawassa University Comprehensive and Specialized Hospital over 5 years from December 2015 to April 2021. Data was collected from 422 medical records using a pretested structured questionnaire. Descriptive statistics to describe the study variables. The association between independent variables with outcomes of abdominal wall defect the variables were examined by using multivariable logistic regression. Statistical significance declared if the P-value is less than 0.05. Result: A total of 420 medical records were reviewed with a response rate of 99.5%. The magnitude of the abdominal wall defect was 40 (9.5%) and from infants who had abdominal wall defect, 6.9% was omphalocele and 2.6% was gastroschisis. Male infants were 8.15 times {AOR=8.15, 95%CI (3.47-19.16)} more likely had abdominal wall defect compared to female infant. Infants from urban residence were 0.36 times {AOR=0.36, 95%CI (0.13-0.97)} less likely had abdominal wall defect compared to infants from rural residence. Conclusion and recommendations: This study showed that the magnitude abdominal wall defect at HUCSH over 5 years. The result of this study was new for study area as well as Ethiopia, there should be farther similar study should be conducted to support the result of this findings.