The article examines the problem of the participation of soldiers from Bohemia in the events of the Battle of Grunwald, both on the side of the Polish-Lithuanian forces and on the side of the Teutonic Order. The state of research of the topic, its place in the study of Grunwald is outlined. The urgency of studying the Czech military component in the armies of both sides was emphasized, given the need to further debunk the myth of the German danger and the pan-Slavic alliance. The author analyzes which Polish-Lithuanian and Order banners fought Czech mercenaries and names the names of their leaders known from sources. The “Czech” episodes in the work of Jan Dlugosz are analyzed, it is noted that the version of the participation of mercenaries from Bohemia in the battle reflects the negative attitude of the Polish chronicler to the Czech Republic. The issue of participation in the events of the war with the Order of the future leader of the Hussites Jan Žižka was raised, the opinion is defended that he fought in the ranks of the Polish-Lithuanian army. Attention is drawn to the involvement of Lithuanian-Rus’ Prince Zygmunt Korybutovych in the Battle of Grunwald, as well as to his further role in Czech-Rus’ relations in the wake of Hussite events. It is noted that the Battle of Grunwald was a decisive event that influenced the gradual withdrawal of Bohemia from the alliance with the Order, at least for those of its forces who later participated in the Hussite events and established contact with Wladyslaw II Jagiello and Vytautas. An episode of Jan Hus's correspondence with the Polish king is mentioned in the context of how Polish propaganda created the myth of its own peace victory immediately after the war. The author concludes that the events of the Battle of Grunwald partly determined for Bohemia its further geopolitical cooperation in Central and Eastern Europe and contributed to the restoration of communication with Lithuania, Poland and Rus’. At the same time, it was emphasized that Grunwald did not become the final severance of relations with the Order, with which Bohemia, like the Kingdom of Rus’, had had strong ties for centuries.