Etoxazole is a member of the diphenyl oxazoline class of insecticide, which was newly developed for use on pome fruits, cotton and strawberries as an acaricide. In the present study, genotoxic effects of acaricide etoxazole (ETX) (miticide/ovicide) were investigated using chromosome aberration ( CA) test, sister chromatid exchange ( SCE) test, and micronucleus test in human lymphocytes. ETX induced the CAs at all concentrations (5, 10, and 20 mug/ml) for 24 h and also induced the CA at the highest concentration (20 mug/ml) for 48 h only. The inducing the CAs for 48 h treatment period was dose-dependent. In addition, it induced the SCE at all concentrations and treatment periods in a dose-dependent manner as well. Although ETX decreased the mitotic index (MI) at all concentrations and treatment periods dose-dependently, it did not decrease the replication index ( RI) when compared to the negative and solvent controls. In addition, ETX induced the micronucleus at all concentrations except 5 mug/ml for 48 h. This inducing was dose-dependent as well. It can be concluded that ETX has a potential genotoxic effects in cultured human peripheral lymphocytes.