A pillar of sustainable development (SD), environmental commitment is the subject of many academic studies often devoted to large enterprises located in developed countries. This article analyzes the environmental commitment of SMEs in terms of public policies in favor of SD in two national contexts, namely France and Tunisia, based on a frame of reference of entrepreneurs' profile. The deductive qualitative methodological approach is essentially based on analysis of interviews conducted in twelve SMEs in each country. The results show that the environmental commitment of SMEs and their motivations are influenced by the managers' entrepreneurial characteristics as well as their education level, degree of innovation and integration in social networks. The comparative analysis shows convergence and divergence between the French and Tunisian contexts, particularly because of public policy, a mirror image of national cultures.