Objective To describe the gastrointestinal function among toddlers (12-36 months) and explore its potential influencing factors.Methods A total of 385 toddlers aged 12-36 months were recruited from September 2018 and January 2019 in a community health service center in Chaoyang District, Beijing. Characteristics of toddlers and their mothers were collected, and the gastrointestinal function of toddlers was evaluated using a simplified Infant Gastrointestinal Symptom Questionnaire (IGSQ). The questionnaire included 10 questions which reflected gastrointestinal symptoms (6 questions) and related behaviors (4 questions). The total score of gastrointestinal function ranged from 10 to 60, among which symptom score ranged from 6 to 36 and related behavior score ranged from 4 to 24. The higher the score indicated that the worse the gastrointestinal function was, and the total score equal to or higher than the second tertiles (score=17) was defined as mild gastrointestinal discomfort. Multivariate logistic regression was used to analyze the potential influencing factors of mild gastrointestinal discomfort.Results The medians (interquartile ranges) of total gastrointestinal function score, symptom score and related behavior score were 13.0 (11.0-19.0), 6.0 (6.0-10.0) and 6.0 (5.0-8.0), respectively. The median score of total gastrointestinal function score was significantly higher in younger (14.5 among toddles aged 12-17 months, 13.0 among toddles aged 18-23 months) than older toddlers (12.5 among toddles aged 24-29 months, 12.0 among toddles aged 30-36 months), and higher in toddlers delivered by primipara (14.0) than in those by multipara (12.0) (P<0.05). Among the 385 toddlers, 124 (32.2%) had mild gastrointestinal discomfort. The incidence of mild gastrointestinal discomfort was significantly higher in toddlers delivered by primipara (36.8%) than in those by multipara (21.8%) (P=0.004). The multivariate logistic regression analyses showed that the risk of mild gastrointestinal discomfort was significantly higher in toddlers aged 12-17 months compared to those aged 30-36 months (adjusted OR, 2.32; 95% CI, 1.14-4.71), and in toddlers delivered by primipara compared to those by multipara (adjusted OR, 2.05; 95% CI, 1.19-3.52). The risk of mild gastrointestinal discomfort was not significantly affected by sex, delivery mode, duration of breastfeeding and maternal age at delivery.Conclusion Toddlers in our study had a generally good gastrointestinal function. Age of toddlers and maternal parity might influence gastrointestinal function. Younger toddlers and those delivered by primipara mother had a higher risk of mild gastrointestinal discomfort.