The goal of the article is to present scope and conditions of the social media use in the internal communication of enterprises operating on the Polish market, as well as what benefits and negative effects of using these media in this communication they notice. Moreover, the article is to present the conditions indicated by the surveyed companies, the fulfillment of which will increase the effectiveness of communication activities based on social media. The research procedure used in the article included literature studies and the analysis of the results of a survey conducted in 2022 using the CATI technique on a sample of 152 companies operating on the Polish market. The respondents were people responsible for the use of Internet technology in marketing activities of their companies, in particular in internal and external communication of these companies. Based on the obtained results, it can be concluded that the level of using social media in internal communication, especially in small and medium-sized enterprises, is still insufficient, but the prospects for using these media are promising, as evidenced by the benefits perceived by the surveyed companies. Enterprises also notice barriers in the use of these media, related to the lack of a social media management strategy developed by the company and related to the lack of integration of social media activities with other communication channels used. Employees' competences to manage communication in social media are also insufficient. The results of the research made it possible to determine the directions of actions, that are necessary in order to increase the effectiveness of the social media use in the enterprise's management of internal and external communication processes.