The 36th Reserve Infantry Division (36 Rezerwowa Dywizja Piechoty) was a unit of the Polish Army in the interbellum period, which took part in the Polish September Campaign. It was formed out of several brigades of the Border Defence Corps of the Podolia region, which had guarded southeastern border of Poland (see: Kresy). In the first days of September 1939, under Colonel Boleslaw Ostrowski, the Division was concentrated in the area of Szydłowiec, as part of the Prusy Army. Facing the Poles was the Second Armored Division of the Wehrmacht, whose units attacked Przedborz on September 3 and after heavy fights managed to capture the town.