This review aimed to synthesise studies examining the presence of gender stereotypes and biases expressed by young children aged 3-5 years, with a focus on informing early childhood settings. Our review located only 21 separate studies in 16 articles, highlighting a dearth of research in this area. There was substantial heterogeneity in the operationalisation of gender stereotypes and biases. There was evidence that children in early childhood are aware of, and can apply, gender stereotypes. There was also evidence of the malleability of these biases and stereotypes. The social and cultural environment plays a large role in defining the cues by which young children classify on the basis of gender. Research is needed to understand ways to support the establishment of equitable gender attitudes amongst children in early childhood, as this could deliver important benefits to individuals across their lifetime, as well as society more broadly.