BACKGROUND : Although sapovirus (SaV) has been detected in 2.2–12.7% of gastroenteritis cases globally,there are limited data on SaV epidemiology. OBJECTIVES : Describe the epidemiology, clinical characteristics and factors associated with SaV gastroen-teritis in hospitalised children <5 years of age in South Africa.Study design: Between 2009 and 2013 during prospective diarrhoeal surveillance, stool specimens werecollected from four sites and screened for SaVs and associated enteric pathogens using ELISA, microscopy,conventional and real-time PCR. Epidemiological and clinical data were compared in patients withor without SaV. Odds ratios were assessed by bivariate and stepwise multivariable logistic regressionanalysis. RESULTS : Sapoviruses were detected in 7.7% (238/3103) of children admitted to hospital and 11.4% (9/79)of deaths. Sapovirus was detected more commonly in children 19–24 months compared to <6 months(aOR = 2.3; p = 0.018) and in males (aOR = 2.0; p = 0.001). Additional factors associated with SaV detectionincluded residing with ≥ 7 inhabitants compared to ≤3 (aOR = 2.2; p = 0.011) and concomitant norovirusinfections (aOR = 3.0; p = 0.003). HIV-infected children with SaV were more likely to have bloody stools(aOR = 16.8; p < 0.001), low birth weight (<2.5 kg; aOR = 5.8; p = 0.007) and live in environments withoutflush toilets (aOR = 8.1; p = 0.003) compared to HIV-uninfected children. CONCLUSIONS : Sapoviruses, which are perceived to cause mild diarrhoea, were detected in hospitalisedchildren and diarrhoeal deaths in South Africa. Determinants increasing the odds of SaV included over-crowding and concomitant infections while HIV-infected children with SaV displayed bloody stools, lowbirth weight and reduced access to proper sanitation. Mitigation strategies against SaV infections includeimproved sanitation.