The sustainability approach applied to tourism has been taking shape as a dominant paradigm in tourism research, as well as becoming a requirement to achieve tourism competitiveness. This paper focuses specifically on the application of both concepts to protected areas, as tourist destinations. A bibliometric approach is adopted to provide information about the patterns and trends in the accumulation of knowledge related to this field, as well as to map its social, conceptual, and intellectual structure. Both evaluative and relational techniques are used to analyse the papers published until August 2019 and collected in the Web of Science (WoS) and Scopus databases. The results indicate that the research field has experienced significant growth in the last decade, with institutions of the USA and Australia as stimuli of scientific progress in this field. This study finds eight thematic clusters, although there is subject dispersion within each cluster, linked to the emerging and multidisciplinary nature of the field. Based on the working lines open, the study also identifies possible future approaches, linked to the incorporation of the perspectives and objectives of the different stakeholders, and the development of indicators to monitor and control dimensions of interest.