The Río Quilquihue is a stream in Neuquén, Argentina, originating at Lago Lolog and flowing toward a confluence with the Río Chimehuin. Its coordinates place it at approximately 40°03′31.7″S, 71°04′0.1″W, in the lake district of Neuquén province.

Access from San Martín de los Andes involves roughly 12 kilometers of gravel road (Ruta 62) to reach the Lago Lolog area. A bridge crosses the river near the lake, and turning right just past the bridge leads to the riverbank. The river features a section of rapids that has been used for whitewater kayak training and racing, with kayakers actively using the course. A small lagoon or backwater near the bridge forms a calmer pool, described as a kidney-shaped bend in the river, which provides a contrast to the faster water around the corner.

The river holds both rainbow trout and brown trout. Fish in the main river tend to run between 500 grams and 1.2 kilograms, while larger specimens exceeding 2 kilograms are more commonly encountered near the confluence with the Río Chimehuin, approximately 500 meters downstream. This confluence zone may be of interest to paddlers looking to extend a run toward the Chimehuin.

Paddlers planning a trip should seek current local information from outfitters or guides based in San Martín de los Andes before committing to a route, particularly regarding seasonal flow patterns, water temperature, formal put-in and take-out infrastructure, and any applicable regulations.