Subject and purpose of work: The purpose of the study is to analyse the structure and the relation of the Polish-Belarusian cross-border cooperation network, to identify the key nodes in the network, to analyse the dynamics of connections between the actors, and to identify the most important changes in the structure of the network. Materials and methods: The article quotes the results of analyses of cross-border projects from 2004- 2017. The analysis includes projects completed, applicants, and partners of projects. The network analysis was carried out using Ucinet and NetDraw software. Results: The structure of the Polish-Belarusian cooperation is dominated by several large nodes, on the other hand there are many micronetworks – of three or four nodes, which are connected with each other. Conclusions: The Polish-Belarusian cooperation is of great importance for the international relations of the Polish state. Projects carried out by entities located at the border strengthen the cooperation, bringing a number of measurable benefits (hard and soft), depending on nature of the projects, as well as frequency and scale of the undertaken activities.