Social media have been a phenomenon in modern society for quite a long time. They have their social importance and are a daily factor in the life of a social actor. Archival science is the science of studying, collecting, selecting, protecting and preserving archival material, and making it available to scientists and researchers. Archivists should be extremely interested in the long-term preservation of the social media content because social media serve as a mediator of communication between social actors. By summarizing the content of social media, one can gain insight into the current state of affairs and the status quo of society. For the purpose of the thesis, a qualitative research was carried out, which examined all state archives in Republic of Croatia. The goal of the research was to gain insight into whether or not state archives preserve the content of social networks, whether they think that archiving content of social networks is important, and the reasons why certain state archives do not archive the content of social networks. The thesis deals with archival theory, construction of technology, theory of collective memory, methods of archiving social network content, appraisal of social media content, national social media archives, digital archiving, social media content archives themselves, research methodology and analysis of research results.