Khanui River () is a river flowing down through the valleys of the Khangai Mountains in central Mongolia. It starts in the Chuluut sum of Arkhangai aimag at the north slopes of the Khan-ÃÂndör mountain. It passes next to the center of Erdenemandal sum, and ends in the Khutag-ÃÂndör sum of Bulgan aimag where it discharges into Selenga River. It is long, and has a drainage basin of .
In 2014, around 0.5 million m<sup>3</sup> of water was withdrawn from the river for livestock, cropland and industrial use.