Objective To investigate the effects of different feeding methods on the early development of small-for-gestational-age (SGA) infants, and to provide clinical evidence for feeding strategies in SGA children. Methods SGA children born at the Department of Obstetrics, People''s Hospital of Dujiangyan City from April 2022 to April 2025 and systematically managed in the pediatric outpatient clinic were selected. They were divided into exclusive breastfeeding group, mixed feeding group, and formula feeding group according to feeding methods. Appropriate-for-gestational-age (AGA) infants born during the same period were selected as controls. Physical growth and neuropsychological development were compared among groups. Results 1. At 3 months of age, the weight Z-score and incidence of catch-up growth in height, and at 6 months of age, the incidence of catch-up growth in weight were significantly lower in the exclusive breastfeeding group than in the formula feeding group; after 6 months, the differences gradually decreased and showed no statistical significance. 2. The incidence of obesity was significantly lower in the exclusive breastfeeding group than in the formula feeding group. 3. No statistically significant difference was found in head circumference Z-scores. 4. The developmental quotients for language, adaptive ability, and social behavior in the formula-fed SGA group were significantly lower than those in the AGA group and the exclusive breastfeeding group; no statistically significant differences were observed between the exclusive breastfeeding group and the AGA group across all developmental dimensions. Conclusion 1. Exclusive breastfeeding in SGA children aged 0–12 months demonstrates more uniform and sustained catch-up growth with a more stable growth rate. 2. Different feeding methods do not affect the physical catch-up growth outcome of SGA children at 12 months of age, but exclusive breastfeeding is associated with a lower risk of obesity. 3. Most SGA children achieve catch-up growth within the first year of life, especially before 6 months of age. 4. Exclusively breastfed SGA children exhibit higher levels of neuropsychological development, comparable to those of AGA children.