The objective of this research was to explore the perceptions of librarians and information professionals of public federal and state university libraries in Brazil located at the front of the potential impact of the open access movement (OA) to scientific literature. This research adopted a qualitative-quantitative methodological approach. A questionnaire was created, adapted from that of Palmer, Dill and Christie (2009), which profiled the professional responsible for university digital libraries and institutional repositories in the United States, adapting it to the Brazilian scenario. 1125 questionnaires were sent to librarians of all the federal universities in Brazil, and to one university in each state, and 244 completed questionnaires were obtained in full, totalling 21.68%. The results identified that the librarians of public universities in Brazil understand the concept of OA, and most of them strongly agree that OA can fail in that country without the involvement of university libraries. Most of the respondents are engaged in the process of promoting and encouraging OA within their institutions and libraries. Regarding their education and training, the vast majority graduated this century (between 2000 and 2012), and 65% have a postgraduate specialization course / MBA, mainly in the areas of Management and Public Libraries. To conclude, it is understood that in general, the results show that the librarians of Brazilian public federal and state university libraries accept the precepts and principles of OA, regarding that they have a crucial role in promoting it, and feel empowered to deal with the challenges it brings, and they are seeking various forms of continued professional development.