The Khalkh River (also spelled as Khalkha River; Mongolian: Халх гол; Chinese: 哈拉哈河; pinyin: Hālāhā Hé) is a river in eastern Mongolia and northern China's Inner Mongolia region. The river is also referred to with the genitive suffix -iin as the Khalkhyn Gol or River of Khalkh
The river's source is in the Greater Khingan mountains of Inner Mongolia. By the mouth it splits into two distributaries. The left one (Halh River proper) feeds the Buir Lake and next via this lake continues as Orchun Gol. The right one Shariljiin Gol (Mongolian: Шарилжийн гол) runs directly into the Orchun Gol.