The Zay is a river in Russia, a left-bank tributary of the Kama. It is 219 kilometres (136 mi) long, and its drainage basin covers 5,020 square kilometres (1,940 mi2). It begins near Mikhaylovka, Leninogorsky District, Tatarstan and falls to the Kama 7 kilometres (4 mi) south-west of Nizhnekamsk.