The succession of financial crises around the world has led many firms, particularly SMEs given their vulnerability, to begin a process of reducing costs. With the media coverage of some audit scandals, the question of the contribution of auditing to some SMEs has been raised in several countries, and some governments have reviewed their audit regulations and exempted some SMEs from auditing on the grounds that its usefulness has not been proven. While in other countries, a debate on the issue is ongoing, and Morocco is not exempt. This raises the question of whether the legal audit, beyond its legal legitimacy, has a legitimacy of socialization among SMEs. However, legitimacy being a sociological concept, its operationalization in the field of management sciences, and particularly in audit research, is not common. The aim of this research paper is precisely to respond to the scientific problem of how to operationalize this concept to analyze the legitimacy of legal audit in SMEs. To this purpose, it proposes a theoretical canvas of analysis, built according to Suchman's (1995) approach to legitimacy, which synthesize both the strategic vision (Aldrich and Fiol, 1994) and the institutional vision (Hybels, 1995) of legitimacy.