Lead (Pb) is one of the major common environmental pollutants. Although, it is not an essential element for plants, plants absorb this element when it availability in their environment is very high, especially in the soil of industrial areas and also in the soil of rural areas that pollutant by applying fertilizers that containing heavy metal impurities. It has lots of toxic effects on plant growth, physiology, and biochemical activities. The aim of present study was to determine the effect of Pb on growth, biochemical and physiological parameters of seedlings of wheat, and to evaluate the sensitivity of wheat to Pb as a basis of selection criteria under unfavourable environmental. Six levels of Pb concentrations such as 0 (as a control), 0.1, 0.25, 0.5, 1.0 and 5.0 mM were imposed on young seedling of wheat cultivar Triticum aestivum cv. Sagittario under complete randomized complete design with four replications in a growth chamber. Results indicated that, the increasing levels of Pb concentration inhibited the seedling growth through reducing the root-shoot length and their dry weight and also reduced the pigment content. While under the maximum concentration of Pb (5.0 mM) lead, proline, ascorbic acid and sulfhydryl groups' content in affected plants were increased. Therefore, it is confirmed that high concentration of Pb (5.0 mM) has a negative impacts on plant growth, physiology and biochemical activities of Triticum aestivum cv. Sagittario, that ultimately affect the photosynthetic pigments, proline, ascorbic acid and sulfhydryl groups of affected plants.