BACKGROUND: Gastroenteritis is a leading cause of childhood morbidity worldwide. We aimed to assess the maternal and infant characteristics and population attributable fractions associated with childhood gastroenteritis-related hospitalizations. METHODS: We conducted a whole-of-population retrospective birth cohort study of 367,476 children live-born in Western Australia 2000-2012. We identified hospital admissions up to <15 years of age pertaining to these children, with a principal diagnosis code for infectious gastroenteritis. Cox regression was used to obtain the adjusted hazard ratios with 95% confidence intervals and the population attributable fractions associated with each risk factor in Aboriginal and non-Aboriginal children for their first gastroenteritis-related hospital admission. RESULTS: There were a total of 15,888 gastroenteritis-related hospital admissions (25.7% occurring among non-Aboriginal children). The overall gastroenteritis hospitalization rate for children <15 years of age was 4.6/1000 child-years for non-Aboriginal children and 21.5/1000 child-years for Aboriginal children. Male gender, <20 years of maternal age, preterm birth, low birth weight, residence in remote regions of Western Australia and birth in the pre-rotavirus vaccine era were significant independent risk factors for gastroenteritis hospitalization in both Aboriginal and non-Aboriginal children. Additionally, birth by caesarean section and low socioeconomic status were identified as being associated with gastroenteritis hospitalization in non-Aboriginal children. Population attributable fractions suggest that 39% of all gastroenteritis hospitalizations in non-Aboriginal children (38% in Aboriginal children) could be averted if all children receive the rotavirus vaccine. CONCLUSIONS: Given the beneficial effect of infant rotavirus vaccination in preventing all-cause gastroenteritis hospitalization, efforts should be taken to optimize rotavirus vaccine coverage in those at highest risk.