The Byosyuke (Russian: Бёсюке; Yakut: Бөөһүкэ) is a river in the Sakha Republic (Yakutia), Russia.

[1] The river flows north of the Arctic Circle across desolate areas of Bulunsky District.

The nearest inhabited place is Kyusyur, located on the banks of the Lena, over 60 km (37 mi) northeast of its mouth.

It flows roughly northwestwards, parallel to the Tikyan, skirting the northern limit of the Dzhardzhan Range and descending into a floodplain in its middle course.

Towards the end it bends westwards and then southwestwards, forking into two in its last stretch and joining the right bank of the Lena 296 km (184 mi) from its mouth.