Luzha River (Russian: Лужа) is a river in Kaluga Oblast in Russia, which originates in Moscow Oblast. It is a right tributary of the Protva River (Oka's basin). The length of the river is 159 km (99 mi). The area of its drainage basin is 1,400 km2 (540 sq mi). The Luzha freezes up in November (rarely in December) and breaks up in April. The town of Maloyaroslavets, the site of an important battle during the French invasion of Russia, is located on the Luzha River.