The Wiązownica massacre occurred on 17 April 1945 in the village Wiązownica, located in Jarosław County Subcarpathian Voivodeship, in southeastern Poland, then located in Lwów Voivodeship. It was one of the Massacres of Poles in Volhynia and Eastern Galicia, and was perpetrated by the Ukrainian Insurgent Army (UPA). The massacre occurred during a battle fought between the UPA and, initially, local Polish partisans, and, later, the Polish People's Army (LWP), towards the outskirts of Wiązownica. It saw the deaths of 91 civilians, including 20 women and children, alongside four LWP soldiers.Grzegorz Motyka, Od rzezi wołyńskiej do akcji „Wisła”, Kraków 2011, , s. 366 The UPA also burned down 150 houses. In retaliation for the attack, the LWP led an attack on the village Piskorowice, given its large concentration of Ukrainians sympathetic for OUN.
