The participation of citizens in creating urban green spaces is a promising approach to promoting health and wellbeing while facilitating the development of equitable cities more prepared for the challenges of climate change. This systematic review provides an overview of the current state of knowledge by synthesizing and summarizing scholarly articles reporting studies on the health effects of participation in green space creation. A review protocol was preregistered on PROSPERO (registration number CRD42023454363). Following PRISMA guidelines, we searched six databases for studies published since 2003. After screening 2676 records, we found 133 studies matching our inclusion criteria and summarized the findings on health effects in qualitative and quantitative research, differentiating between study types, population types, and intervention types. In addition, we explored secondary outcomes mentioned in the included articles. The majority of studies reported positive impacts of participatory green space creation on general, mental, and physical health. Moreover, many studies reported other personal and social benefits. The results of this review indicate that the participatory creation of urban green spaces represents a promising approach to promoting health and wellbeing. Nevertheless, further high-quality, quantitative research is required to gain a more comprehensive understanding of the relationship between participatory green space activities and health, particularly with regard to the benefits of specific intervention types and subpopulations.