The Tyukyan (Russian: Тюкян; Yakut: Түүкээн Tüükeen) is a river in the Republic of Sakha in Russia. It is a left hand tributary of the Vilyuy, and is 747 kilometres (464 mi) long, with a drainage basin of 16,300 square kilometres (6,300 mi2). There are no permanent settlements by the river, but its source lies close to Eyik village in Olenyoksky District. After flowing across desolate areas it only reaches the inhabited Verkhnevilyuysky District about 50 km (31 mi) upstream from its mouth.
