Antineoplastic agents due to their cytotoxic effects increase the amount of free radical in cells causing cell death. The aims of this study were to assess the possible toxic effects of Bleomycin (BLM) on the number of offspring and survival rate of fruit flies as well as the protective role of Berberis crataegina DC. fruit extracts (BCE) on these effects. Solutions prepared in different concentrations (0.125 mg/mL for BLM; 10 and 20 mg/mL for BCE) were applied to the adult fruit fly Drosophila melanogaster's wild-type individuals and 72 +/- 4 h larvae to determine the number of offspring and survival rate, respectively. As a result, the higher number of offspring and survival rate in the BCE + BLM applied groups than the only BLM applied groups shows that BCE is an antioxidant and has a protective effect (p<0.05). This protective effect can be explained as the prevention or removal of the free radicals formation from the environment.