Objective To analyze the physical and neuromotor development characteristics and existing problems of extremely preterm infants in the earlylife stage(0 to 2 years old), so as to provide scientific basis for improving the long-term quality of life of extremely preterm infants. Methods The physical development data of 258 extremely preterm infants followed up in the high-risk infant clinic of Shenzhen Maternity & Child Healthcare Hospital from 2016 to 2019 were analyzed and compared with the physical development data of children aged 0 to 2 years in nine cities of China in 2005. Physical development indicators(weight, length and head circumference), the standard deviation Z and the distribution of each indicator less than the 10th percentile(＜P₁₀) and less than the 3th percentile(＜P₃) were compared among different age groups. The development of infants was evaluated by Bayley Ⅱ Infant Scale at the corrected age of 6, 12, 18 and 24 months. Results 1) At the corrected age of 2 years old, the physical catch-up development of extremely preterm infants was still not ideal, in which the body length was better, followed by the weight, while the head circumference developed most slowly. The Z values of body length, weight and head circumference of boys were -0.31, -0.51, -0.87, and those of girls were -0.22, -0.43, -0.54. 2) The proportions of length, weight and head circumference <P₁₀ and <P₃ in extremely preterm infants within corrected age of 2 years old were significantly higher than the theoretical values for children with the same age. For boys at the corrected age of 2 years old, the corresponding values of body length, weight and head circumference < P₁₀ were 17.78, 22.22 and 28.89, respectively, while the corresponding values of body length, weight and head circumference < P₃ were 2.22, 13.33 and 15.56, respectively. For girls at the corrected age of 2 years old, the corresponding values of body length, weight and head circumference < P₁₀ were 13.04, 26.09 and 21.73, respectively, while the corresponding values of body length, weight and head circumference < P₃ were 8.70, 17.39 and 13.04, respectively. The proportions of body length and weight < P₁₀ decreased with age, and the proportion of head circumference maintained a high level within 2 years old. 3) The intelligence and motor development level of extremely preterm infants at the corrected age of 2 years old had a large gap with that of full-term infants with the same age. There was an upward trend of gradually catching up within the age of 2 years. The development of girls was slightly better than that of boys, but the difference was not significant(P>0.05). Conclusions 1) The physical development within corrected age of 2 years old after preterm birth is still not complete catch-up development. The catch-up of body length is ideal, followed by body weight, while the catch-up of head circumference is the slowest. Early nutrition enhancement should be focused on the improvement of head circumference and body weight. 2) The motor and intellectual development of extremely preterm infants within the corrected age of 2 years old shows a gradual increase, but there is a large gap compared to children of the same age and intensive training should be provided until 2 years old.