Social networks have reached a very significant presence in the communication of organizations and are changing the way they disseminate information and interact with their audiences.Museums are also using these communication platforms, approaching the idea of "social museum" or "Museum 2.0".In this sense, the main objective of this article is to evaluate the presence and activity on Facebook (the largest social network) of the most visited art museums in Spain and worldwide.The results of this paper indicate that Spanish museums are in a similar situation and, in some respects, better than international museums, although it is true that there is still ample room for improvement in the extent to which it is not exploring the capacity enough for dialogue of these technological tools.