Introduction and objective: The presentation of the challenges Poland faces in the military security of the state in the context of Russian aggression on Ukraine. Material and methods: Analysis of the documents, mass media materials and other researchers works. Results: Identification of the nature of the challenges and methods to deal with them. Conclusions: Russia is the main challenge for Poland. Poland’s insufficient potential in the context of the Russian threat forces it to look for additional, external sources of strength. There are three of them: 1) USA/NATO; 2) Other nations in similar situation with a particular importance of Ukraine and the most determined – the Baltic States 3) EU – which however is getting weaker. Own Polish armaments, close cooperation with the U.S. based on the Polish will and capacity to contribute to the common transatlantic security as a leading US ally in the region, close cooperation with Ukraine and the Baltic states are the recommended methods to meet the Russian challenge.