Optimal child development is supported by services, policies, a social determinants of health (SDOH) frame, and meaningful participation (as defined by the International Classification of Functioning, Disability, and Health–Children and Youth [ICF-CY]). This scoping review describes the social determinants that may affect the participation of young children aged 0 to 3 years with developmental disabilities (DD) in the United States. Scoping review of studies including U.S. children with DD aged 0 to 3 years, from 2000 to 2016, were used. 5/979 studies met inclusion criteria. Two researchers independently coded studies to align them with both ICF-CY and SDOH. Studies found determinants of participation stemming from the child (e.g., individual) and multiple contexts: immediate, community, and policy. The emergent literature continues to primarily focus on child determinants but suggests participation of young children with DD is affected by social determinants stemming from the community and policy contexts. The literature underrepresents children from racial/ethnic minority backgrounds.