Social enterprises need to develop processes that create social value to solve social problems. The purpose of this investigation was to examine the effect of marketing capability on social innovation and its effect on social and economic value creation, while controlling for firm size among social enterprises in Mexico. An explanatory and cross-sectional design was used to test the hypotheses: 118 social business managers were interviewed and structural equation modeling was used to test our research hypotheses. The results supported our proposition that marketing capability influenced social innovation, which then had a positive influence on social, though not on economic value creation. An indirect effect from marketing capability to social value was also found. This study validated the relevance of defining and entailing marketing capabilities with social innovation strategies and their effect on the social value of social enterprises. This paper contributes to a better understanding of marketing capability and its effects on social innovation in social enterprises. In addition, it shows social innovation to be a robust predictor of social value, with important implications for social and economic sustainability.