This study examines the genotoxic effects of coumarin (2H-1-benzopyran-2-one) on Lens culinaris Medik cv Sultan in terms of DNA polymorphism and protein quantification. Effective concentration values were calculated according to a probit model, which is a type of regression where the dependent variable can take only two values, i.e., life or death, after 48 or 72 h of treatment. Based on this analysis, the effective concentration value of EC50 identified as approximately 278 mu M, and then adjusted to 300 mu M. The bulb roots were treated with 300 mu M (EC50), 600 mu M (2X EC50) concentrations and the Hoagland was used in the control group.10 RAPD primers were used and as a result of the analysis, it was observed that 2 monomorphic and 8 polymorphic band profile primers for treatment of 600 and 300 mu M, coumarin concentration according to the control group. Total of 39 polymorphic bands were detected from total of 97 bands and the percentage of polymorphism was detected as 48.75%. SDS-PAGE analysis for total protein profile showed that there were differences between the treatment groups. In addition to PCR analysis, the root samples were examined by Fourier transform infrared (FT-IR) spectroscopy in order to determine the effects of coumarin on the quantity of biomolecules structure of L. culinaris One-way analysis of variance (ANOVA) was used in the calculation of statistical differences between the groups (P < 0.05).