Over 80% of preschool-aged children experience non-parental childcare. Childcare type has the potential to influence weight outcomes, but its impact on childhood overweight/obesity is not well established. This review aims to (i) systematically evaluate the effects of childcare type on childhood overweight/obesity risk and (ii) investigate the impact of childcare intensity and age at commencement. Five electronic databases were searched for observational studies quantifying an association between childcare type ≤5 years and weight outcomes