Bothrops snake venoms have been proved toxic to a variety of cell types, in both in vivo and in vitro models. Studies on the pharmacological actions of Bothrops venoms from Argentina are relatively scarce and the direct action of the crude venoms has not been assessed using cell culture models. In this work, we investigated the cytotoxicity of crude venoms from B. alternatus and B. diporus in a skeletal muscle (C2C12) cell line, which is commonly used as a model for studying the myotoxic action of snake venom. Both venoms (1.25-50 μg/mL) induced an early and significant decrease in cell viability. The cytotoxic concentration 50 (CC50), determined three hours after exposure, revealed that B. diporus venom was significantly more cytotoxic (CC50: 2 μg/mL) than B. alternatus (CC50: 5.8 μg/mL). To investigate the cell death mechanism involved, myoblast cells were examined by phase contrast microscopy and after acridine orange and ethidium bromide fluorescence staining, respectively. Our data clearly demonstrated that an apoptotic mechanism mediated this cell line destruction. The current study aimed to provide new information on the cytotoxicity mechanisms of Argentine Bothrops snake venoms on a skeletal muscle cell line.