Abstract: The pesticides possess biological activity including genotoxic influence and can influence non target organisms. Oxyfluorfen (2-chloro-1-(3-ethoxy-4-nitrophenoxy)-4-(trifluoromethyl) benzene) is classified as a possible human carcinogen. In present study cytotoxic and genotoxic effects of commercial formulation of GOAL (oxyfluorfen) were evaluated using Allium cepa assay. The effective concentration (EC50) value determined in root growth inhibition test using T. aestivum L. was 1.2 ml L-1. Allium cepa root tips were exposed to 1.2 ml L-1 (EC50), 0.6 ml L-1 (1/2 EC50) and 0.3 ml L-1 (1/4 EC50) for 24 or 48 h. Mitotic index decreased substantially at 1/2 EC50 and EC50 at both treatment times. The herbicide caused a change in the frequencies of the different mitotic phases. GOAL induced various mitotic abnormalities revealing clastogenic and turbagenic activities. Anaphases and telophases with vagrant chromosomes and fragments were the most frequent kinds of abnormalities. GOAL caused spindle disturbances and produced C-mitotic effect and multipolar anaphases. We also noticed bridges in anaphase and telophase. The percent of chromosome aberrations increased with increasing the concentration and the duration of treatment. Micronucleated cells were observed in interphase cells. The frequency of the micronuclei was markedly higher after 48 h compared to 24 h exposure. In conclusion, the results indicate cytotoxic and genotoxic effect of GOAL in A. cepa root tip cells after exposure for 24 and 48 h at concentrations below commercially recommended.