The objective of this study is to determine the effects of chlorantraniliprole (CHL) pesticide on ATPases (Na+/K+ ATPase, Ca2+ ATPase and Mg2+ ATPase) of gill and muscle in O. niloticus. Fish were exposed to acute and chronic chlorantraniliprole (CHL) exposure (0.5, 1.5 and 3.0 mg/L). UV-vis spectrophotometric methods were used to determining enzymes activity. When compared to control fish, the most inhibitions determined to Ca2+ ATPase > Na+/K+ ATPase > Mg2+ ATPase on gill and muscle tissues. This work showed that Ca2+ ATPase is more sensitive biomarker chlorantraniliprole (CHL) pesticide than other ATPase enzymes. In our study, O. niloticus could be a suitable biomarker for chlorantraniliprole (CHL) and ATPases are very important early warning ecotoxicologic parameters.