Environmental pollution, especially heavy metal pollution, is an important environmental problem all over the world. Heavy metals that accumulate in high concentrations in soil and water ecosystems are known to damage most functional biomolecules such as DNA, RNA and protein in living organisms and cause genotoxicity. For example, cadmium heavy metal is one of the heavy metals that negatively affect plant growth and development. The purpose of this study was to determine the methylcytosine level in the sunflower plant genome and the changes in the methylation pattern under cadmium stress. Sunflower seeds were grown with different concentrations of cadmium heavy metal solution (Control, 20, 40, 80, 160, 320, 640 and 1280 ppm) for 3 weeks. According to the data obtained in the study, as the cadmium concentration increased, the growth and development of sunflower seedlings decreased. After detecting DNA band variations by RAPD analysis, methylcytosine levels in the sample genome were determined by CRED-RA technique. As a result of RAPD analysis, the highest GTS rate was 87.83% at 20 ppm cadmium concentration and the lowest rate was 81.75% at 320 ppm. Four different methylation patterns (Type I-IV) were determined according to the CRED-RA analysis. As a result of the study, significant changes in the DNA methylation pattern were observed by CRED-RA analysis in the sunflower genome exposed to cadmium heavy metal stress.