The present study was carried out to evaluate the effects of heavy metals resulting from steel factories and their impact on contents pigments in five plant species (Olea europaea L., Eucalyptus amygdalina, Nerium oleander L., Dodonaea viscosa, and Phragmites australis) in the city of Erbil. Fe, Cu, Mn, Ni, Zn, As, Pb, Co, chlorophyll a, chlorophyll b, total chlorophyll, carotenoids and total protein were determined in leaves of plants away from the factory used as control (unpolluted site), and plants grown in the garden inside the steel factory (polluted site). The results revealed the significant higher accumulation of all heavy metals in all polluted plants in comparison with unpolluted plants. Higher concentrations of Fe, Zn, As, Pb and Co were recorded in leaves of Dodonaea viscosa, while Olea europaea L. found an accumulation of more concentration of Cu and Ni. The level of Mn is significantly higher in the leaves of Eucalyptus amygdalina when compared with other plants. Plants grown on contaminated sites showed the lower concentration of pigments and protein contents. A negative correlation was found between the concentration of heavy metals, pigments and total protein contents in all plant species.