The paper provides the Length–weight relationships (LWRs) for four endemic snakehead fish species namely Channa andrao Britz, 2013, Channa bleheri Vierke, 1991, Channa aurantimaculata Musikasinthorn, 2000 and Channa stewartii (Playfair, 1876), based on seasonal catches along the Brahmaputra river drainage from October 2016 to May 2018, using cast net (mesh size: 10–20 mm), scoop net (mesh size: 05–10 mm) and bamboo traps. Total lengths (TL) (nearest to 0.1 cm) and body weights (nearest to 0.1 g) were taken respectively. The b values in the LWRs were 3.26 for C. andrao, 2.74 for C. bleheri, 3.04 for C. aurantimaculata, and for 2.78 C. stewartii respectively. For C. aurantimaculata (=36.2 cm), C. bleheri (=14.4 cm) and C. stewartii (=29.7 cm) each, a new maximum total length (TL) was recorded.