Zhizdra River (Russian: Жиздра) is a river in Kaluga Oblast in Russia, Oka's left tributary. The length of the river is 223 km. The area of its basin is 9,170 km². the Zhizdra River freezes up in late November and stays icebound until early April. Its main tributaries are the Resseta, Vytebet, and Serena. The towns of Kozelsk and Zhizdra are located on the shores of the Zhizdra. The name is of Baltic origin (cf. Lithuanianžizdras 'thick sand, gravel').