The article describes the process of developing the Polish-Germany military cooperation in the 21st century. It presents the bases for the bilateral military relationships between Poland and Germany and shows their development. The paper underlines the role of Germany in the Polish participation in NATO. The Author describes the common initiatives after joining the Pact, especially the participation of Bundeswehr in training and technical modernisation of the Polish armed forces. He claims that after the year 2015, the Polish-German military cooperation will be a function of Germany’s pragmatics and Poland’s history politics. The main problem of the Polish government will be the German willingness to constantly build NATO military bases in Poland.