Resumo: Mountain tourism, which includes ski resorts and protected natural areas, has to strike a balance between meeting the needs of visitors and respecting the environment. In the search for this balance, marketing can play an important role. This paper seeks to respond to the lack of studies on the application of marketing in mountain tourism activities and, in particular, in communication in social networks by comparing the application and the perception of marketing in ski resorts with that of natural and national parks. To this end, a marketing audit was carried out, based on interviews with managers and technicians of each and analyzing 26 indicators of social networks (Twitter and Facebook). The ski resorts have a greater focus on marketing except in aspects related to environmental impact. The results show the different levels of sensitivity and those aspects where there is greater divergence, distinguishing the degree of importance and degree of adequacy that is granted by the importance-adequacy matrix. There is also greater dynamism in the social networks of ski resorts.