The river's catchment area includes the major tributaries flowing into Lake Tinaroo including Kauri, Mazlin, McLean, Maroobi, Peterson and Severin Creeks. It also absorbs most of the major tributaries on the Atherton Tableland, including Emerald Creek, Granite Creek, the Clohesy River and Stoney Creek. This also includes Thomatis Creek, which has only been connected to the Barron since 1932 and has been responsible for diverting part of the flow from the river. Freshwater Creek joins the Barron River below the Gorge and drains Lake Morris and the Lamb and Whitfield Ranges.