The Bolshoy Yugan is a river in Russia, it flows through the territory of Surgutsky and Nefteyugansky Districts of Khanty-Mansi Autonomous Okrug. A left tributary of the Ob, it discharges into the Yuganskaya Ob, a branch of the Ob. The length of the river is 1,063-kilometre, its basin area is 34,700-square-kilometre. The average annual water consumption at 118-kilometre from the mouth of the river is 177.67-cubic-metre-per-second.
