The Ala-Buga (, also ÃÂûðñÃÂóð) is a left tributary of the Naryn in Naryn Region of Kyrgyzstan. The river is known as Arpa in its upper reaches; the rivers Arpa and Bychan merge to form the Ala-Buga. The Ala-Buga is formed on the north slopes of the Torugart Range and the south slopes of the Jaman-Too mountains. Flowing eastward through the Arpa Valley, it widens and becomes shallower as it enters the Middle Naryn Valley.
It is long, and has a drainage basin of . It has an average elevation of , an annual average flow rate of , and an average specific discharge of 8.35 L/sâ¢km<sup>2</sup>.
Major tributaries include:
Settlements located along the banks of Ala-Buga include Kosh-Döbö, Jerge-Tal and Kongorchok.