Abstract: Objective To determine the association of eating frequency (EF) and gestational weight gain (GWG) with birth body mass of neonates. Methods A prospective cohort study was conducted on 578 healthy pregnant women from April to October 2015. Dietary intake and physical activity data per trimester were collected using a questionnaire. Data in relation to gestational body mass, gestational stage and birth body mass of neonates were obtained from clinical records. Multiple logistic regression models were established to test the impacts of EF and GWG on appropriate for gestational age (AGA). Multiple linear regression analyses were performed to determine the association between EF and birth body mass of neonates. Results A final sample of 503 eligible pregnant women (87.02%) was included in data analyses. Higher EF 〔odds ratio (OR)=2.03; 95% confidence interval (CI): 1.18-3.47〕 and snacks (OR=1.84; 95%CI: 1.08-3.15) in the first trimester were associated with increased risk of excessive GWG, after controlling for maternal age, education, average household income, physicalactivity, numbers of pregnancy, numbers of delivery, and dietary intake (protein, fat, carbohydrate). A meal frequency greater (OR=2.83; 95%CI: 1.07-4.58) or less (OR=1.92; 95%CI: 1.08-3.61) than three in the first trimester was also associated with increased risk of large or small for gestational age. Meal frequency in the first trimester was positively correlated with birth body mass of neonates (β=236.17; P<0.01). Conclusion Frequent eating and snacks in the first trimester are associated with increased risks of excessive GWG. Meal frequency in the first trimester is also positively correlated with birth body mass of neonates: three meals per day is a protective factor of AGA.