In this study, in vivo genotoxic effects of five food preservatives potassium sorbate (E 202), calcium sorbate (E 203), sodium benzoate (E 211), potassium benzoate (E 212) and calcium benzoate (E 213) which is used as food additives were researched on Drosophila melanogaster haemocytes with Comet assay (single cell gel electrophoresis). D. melanogaster larvae in the third larvae stage have been treated with Standard Drosophila Medium which was mixed with different concentrations (for calcium benzoate, 0.09 mM, 0.18 mM, 0.27 mM, 0.36 mM; for calcium sorbate, 0.01 mM, 0.2 mM, 0.3 mM, 0.4 mM; for potassium benzoate, 0.15 mM, 0.3 mM, 0.45 mM, 0.6 mM; for potassium sorbate, 0.17 mM, 0.34 mM, 0.5 mM, 0.7 mM; for sodium benzoate, 0.175 mM, 0.35 mM, 0.5 mM, 0.7 mM) of these food preservatives for 24 hours. Comet assay method was applied after treatment. DNA tail, tail moment and DNA head were used as evaluation parameters. Statistical data which obtained about results were evaluated with ANOVA Test. As a result of this evaluation, these substances caused an increase for DNA tail and tail moment, caused a decrease for DNA head amount. Also, potassium benzoate is the most genotoxic substance among the substances whose effects are searched.