Polycyclic aromatic hydrocarbons (PAHs) are part of the petroleum contaminants in the environment. PAHs are highly persistent in terrestrial ecosystem which adversely affects both plant and human life. The present work aimed to evaluate the effects of phenanthrene (PHE), a three-ring polycyclic aromatic hydrocarbon, on antioxidative enzymes (peroxidase and catalase), morphological and anatomical changes in root of Festuca arundinacea. Experiment was carried out under greenhouse condition with 4 treatments (0, 80, 300 and 600 mg.kg-1) and 3 replications during 30 days. The activities of catalase (CAT) and peroxidase (POD) increased as the soil PHE concentration increased. Morphological symptoms of phenanthrene stress were reduction of root length and reduction in root hairs. Also anatomical characteristics of root were affected by PHE contamination. The thickness of epidermis, endodermis, phloem, xylem and root diameter increased while size of cortical cells reduced in compared to the control.