The Battle of Soor (30 September 1745) was a battle between Frederick the Great's Prussian army and an Austro-Saxon army led by Prince Charles Alexander of Lorraine during the Second Silesian War (part of the War of the Austrian Succession). The battle occurred in the vicinity of Soor, also known as Hajnice, in the modern day Czech Republic. The battle started with a failed Austrian surprise attack on the outnumbered Prussians.