Objective To explore the risk factors of necrotizing enterocolitis (NEC) in small for gestational age (SGA) neonates. Methods The SGA patients suffering from NEC from January 2008 to December 2021 were selected as the research subjects. The SGA patients without NEC in the same period were selected as the control group, and 1∶2 matching was performed according to gestational age difference <3 d, birth weight difference <200 g, and date of admission difference <3 months. The influencing factors of NEC occurrence in SGA neonates were analyzed by conditional logistic regression. Results A total of 5 365 SGA neonates were admitted during the study period, among whom 147 SGA neonates met the diagnostic criteria of NEC stage Ⅱ or above, and the incidence rate was 2.70%. After screening and exclusion, 140 patients were finally included. A total of 280 SGA neonates were involved in the control group by 1∶2 matching. Compared with the control group, the NEC group had higher rates of anemia, neonatal sepsis, death or treatment abandonment, longer hospital stay, and lower rates of prenatal exposure to glucocorticoids and oral probiotics, and the differences were statistically significant (P<0.05). Conditional logistic regression analysis showed that sepsis and anemia were independent risk factors for NEC in SGA (P<0.05), while prenatal glucocorticoids exposure and oral probiotics were independent protective factors (P<0.05). Conclusions The SGA neonates with anemia and sepsis are more likely to develop NEC, while oral probiotics and prenatal exposure to glucocorticoids can reduce the risk of NEC..