Heavy metal contamination is an important environmental problem all over the world. High concentrations of heavy metals cause permanent damage stocells and tissues. In this study, the toxic effects of zincheavy metal in sunflower plant in population and molecular parameters were investigated. The effects of zincheavymetalon sunflower seedlings were determined using the changes in population parameters; rootlength, dry weight, and total solubleprotein content. Total protein content of sunflower plants was determined in a relationship in the opposite direction increasing the amount of metal concentrations. Genotoxic effects of heavymetal of zinc on sunflower plants were revealed by using changes in genomic template stability (GTS). According to analyses, serious changes in genomic template stability were detected and these results were compared with the growth, dry weight and total soluble protein content of the seedlings grown at various zinc concentrations. Also, it was seen that the genomic template stability significantly affected the primary root length, root dry weight and root total soluble protein content. Positive correlations were observed between physiological, biochemical and molecular parameters in sunflower seedlings under zinc stress.In conclusion, a comparison between physiological, biochemical and molecular parameters shows that zinc is a genotoxic agent for sunflower plants.