To explore the incidence and epidemiological characteristics of developmental dysplasia of hip (DDH) in Lianyungang and provide a basis for early detection, early diagnosis and early treatment. Ultrasound screening was performed on aged 4-6 weeks to collect the incidence and epidemiological profiles of DDH. Graf hip ultrasound imaging was used for screening. DDH was diagnosed with a classification of ≥IIa-. Of the 9803 babies, 4999 were boys and 4687 were girls. There were 117 babies diagnosed with DDH, incidence rate of 1.19%. The incidence of DDH rate at left was higher than that at right (0.89%, 87/9803) vs (0.37%, 36/9803) and the difference was statistically significant (P < 0.001). Multivariate logistic regression analysis indicated that female (OR = 5.059, 95% CI: 3.012-9.109) and first child (OR = 1.871, 95% CI: 1.169-2.832) were the risk factors of DDH. Due to the small number of relevant cases and the absence of DDH cases, improper swaddling, abnormal amniotic fluid volume and confluent malformation could not be included for statistical comparison. The incidence of DDH in infants aged 4-6 weeks in Lianyungang was 1.19% (117/9803). DDH was more prone to occur on the left side. Girl and first-borns were the risk factors of DDH.