In this study, the effects of a porphyrazine derivative, [octakis (2-trimethylammoniumethyl thio) porphy-razinatocobalt] octaiodide (CoPzq), were explored on the developmental characteristics, sex ratio and egg fertility of Drosophila melanogaster. CoPzq was preferred in the study due to its probability to be used as a chemotherapeutic agent in medicine. As a result of the application of CoPzq, a phenotypic abnormality was revealed within the individuals of F-1 and F-2 generation of Drosophila. Although individuals of F-2 generation did not directly come into contact with the chemical, the rate of abnormality is high. An increase was observed within both generations in terms of the egg fertility. Besides, a deviation emerged in the sex-ratio in some concentrations.