The use of social media has advanced in all social strata with effect on citizen participation in political discussions. In the context of Science, Technology and Innovation (ST&I) policies, bringing citizens closer together is a challenge for scientific and governmental institutions. The Brazilian States Research Support Foundations (RSF) show interest in promoting this approach to legitimize investments in science. Studies on the effects of social media on the relations between science, society and government are scarce. This research analyzed how e-participation, through social media, promotes citizen participation in the ST&I policies and actions of the RSFs. Nine organizations, including at least one Foundation from each Brazilian region, participated in this study. The main contribution of social media was the ability to intensify the interactions between government, researchers and citizens, using an informal and accessible language. E-participation can facilitate the approximation of civil society to ST&I activities to deal with these challenges. E-participation is understood as the use of Information and Communication Technologies (ICTs), mainly the Internet, to promote citizen participation in the agenda-setting and decision-making [10][11][12]. Also, it contributes to the citizen participation process by providing communication technologies by making information accessible and creating a broader interaction environment [10]. The improvement of the ICTs brought tools for creating and sharing user content, like Youtube, Twitter and Facebook. The so-called social media broaden the channels of dialogue with multiple actors and higher opinions heterogeneity [13], being one of the most used e-participation tools [14]. The communication and speed are increased at a reduced cost, enabling an equitable participation process [15]. The government can place itself where citizens already are communicating [16]. In contrast, the heterogeneity and the volume of opinions make it difficult for information analysis [13,17,18]. Citizens' interest in participation does not always go well as expected [19,20] and government institutions may not use social media for closer dialogue with citizens [21].Research associating e-participation to the ST&I policies and actions, in particular, using social media as tools is lacking. Ho et al. [22] point out the need for