This research aims to describe and analyse how Swedish dairy companies have maintained legitimacy through their CSR reporting during the period 2000-2018. The research drew on Suchman’s (1995) conceptualization of legitimacy, focusing specifically on the three types of legitimacy strategies: pragmatic, moral, and cognitive legitimacy as well as Hahn & Lüfls’s (2014) legitimacy strategies on adverse aspects. A total of 71 annual and CSR reports were analysed using thematic content analysis and qualitative content analysis. The research found that the companies maintain legitimacy similarly and used all three of the legitimacy strategies by Suchman (1995), but that specific CSR topics brought specific strategies. The main differences concerned the extent to which each company used legitimacy strategies. The companies maintain legitimacy mainly through cognitive legitimacy, which was apparent during the whole investigation period 2000-2018. However, during 2010–2018, the use of moral legitimacy increased in their CSR reporting. Concerning adverse aspects by Hahn & Lüfls (2014), the dairy companies frequently shifted their use of legitimacy strategies following both substantive and symbolic management during the whole investigation period. However, during 2012- 2018, symbolic management was more apparent when the companies disclosed environmental activities.