BackgroundTo fully leverage the potential of the early care and education (ECE) setting for childhood obesity prevention, initiatives must not intervene solely at the organizational level, but rather they should also address the health needs of the ECE workers. Workers suffer disproportionately high rates of obesity, and have reported low confidence in modeling and promoting healthy eating and activity behaviors. However, information regarding the effectiveness of improving ECE workers’ health behaviors or whether such improvements elicit meaningful change in the ECE environment and/or the children in their care is limited.MethodThe proposed study will integrate a staff wellness intervention into a nationally recognized, ECE obesity prevention initiative (Go NAPSACC). Go NAPSACC+ Staff Wellness program will be assessed using a clustered randomized controlled trial including 84 ECE centers, 168 workers, and 672 2–5-year-old children. Centers will be randomly assigned to 1) standard “Go NAPSACC” or 2) Go NAPSACC+ Staff Wellness. Outcome measures will assess impact on dietary intake and PA behaviors of 2-5-year-old children at 6 months (primary aim) and 12 months. Secondarily, we will compare the impact of the intervention on centers’ implementation of healthy weight practices and the effect on ECE workers’ diet quality and PA at 6- and 12 months.DiscussionThis trial expects to increase our understanding of how ECE worker’s personal health behaviors impact the health behaviors of the children in their care and the ECE environment.Trial registrationClinicalTrials.gov:NCT05656807, registered on 19 December 2022. Protocol version 1.0, 22 March 2023.