Objective: Sport may promote academic performance through physiological and psychosocial mechanisms. We aimed to examine the association between sports participation and academic performance in Aboriginal and Torres Strait Islander children. Methods: Participants were from four successive waves of Australia's Longitudinal Study of Indigenous Children (n = 303, baseline age 5-6 y). Cumulative sports participation was regressed against academic performance from two standardised tests. Results: Children participating in sport at all four waves performed significantly better than children participating in sport in 0, 2 or 3 waves in Progressive Achievement Test (PAT) Maths (110 vs. 103, 105 and 105, p = 0.007, 0.02 and 0.02, respectively), and better than children participating at two waves in National Assessment Program -- Literacy and Numeracy (NAPLAN) numeracy (438 vs. 409, p = 0.006). There were no significant differences in PAT reading or NAPLAN literacy. Conclusion: Sports participation appears to be associated with subsequent better numeracy (2-7 months of learning) in a sample of Australian indigenous children. Fostering sports participation among indigenous children may be an avenue for reducing disadvantage.