The issue of trust in international relations seems interesting and certainly merits a thorough examination. Compared to studies of other categories of international relations, those pertaining to trust still remain rather limited, but the sphere is increasingly attracting the attention of internatiologists. The purpose of this article is to expand the studies of international relations and state foreign policy, in particular the Polish ones, to include the category of trust, with special emphasis on Polish–Russian relations. The author has set out to review international relations theories while focusing on trust as well as to outline the notion of trust, its sources and determinants. In addition, the purpose of this article is to provide a preliminary answer to the question about the reasons behind the lack of trust between Poland and Russia.