Recent studies have shown the opportunities and limitations of participatory mapping for ecosystem services management, although it is an incipient research area. One of the research questions yet to be addressed is whether the composition of stakeholder groups has an effect on the outputs of participatory mapping. In this study, we assessed the influence of group composition on the mapped spatial distribution of ecosystem services. We developed two participatory mapping workshops of the ecosystem service supply and demand in the Nacimiento Watershed (Andalusia, Spain). In workshop 1, stakeholders were uniformly grouped according to their level of influence on land management. In workshop 2, we created mixed groups, with participants having dissimilar levels of influence on land management. The strategy of the second workshop aimed to foster social learning among participants, which was expected to influence the mapping outputs. We compared the outputs regarding the mapped spatial distribution of the ecosystem service supply and demand between the two workshops. Our results suggest that social learning occurred in groups with a mixed composition of participants, affecting the mapped spatial distribution of the supply and demand of ecosystem services. Finally, we discuss that knowledge exchange among participants can be supported through deliberative processes that occur in participatory settings, when stakeholders have different degrees of influence on land management. This can also enrich the assessment of the distribution of ecosystem services.