Background: Early childhood development (ECD) practitioners are crucial to young children's motor milestone achievement, motor development and physical activity (PA) participation. Their role in helping young children reach appropriate PA levels and gross motor milestones has not received sufficient attention. Aim: This study examined the contribution of ECD practitioners to the acquisition of gross motor milestones and PA participation in children aged 0-4 years. Setting: A literature search was conducted using specified search terms. Search parameters were set between 1994 and 26 May 2021. Methods: The Manual for Evidence Synthesis was used for this scoping review. The mapping of evidence based on research about the contribution of ECD practitioners to the acquisition of gross motor milestones and sufficient PA levels, particularly in children aged 0-4 years, was performed using the nine stages of the scoping review approach. Results: Early childhood development practitioner-led PA interventions positively influence children's overall PA, especially when thoroughly executed by sufficiently trained practitioners. In addition, ECD practitioners' PA correlated positively with children's PA. Conclusion: Physical activity interventions presented by ECD practitioners might have a positive influence on children's overall PA levels, if interventions were thoroughly executed and ECD practitioners received sufficient training. Gaps identified in the current literature include a lack of longitudinal studies and research investigating ECD practitioners' contribution to young children acquiring gross motor milestones. Contribution: The study contributed to the limited information regarding practitioners' contribution to gross motor milestone acquisition and adequate PA, highlighting several gaps where research is required.