Abstract: In the present study, Rhizobium was used as soil fertilizer to prevent the stress of lead on growing Pisum sativum. Three concentrations of lead were used (50, 100 and 200 ppm.) for the irrigation of growing plants (two times). After sowing, M2 seeds were collected, then cytological and biochemical studies were carried out. The cytological analysis revealed that soil enriched with Rhizobium increased the rate of mitotic division. A significant increase in mitotic index was detected. The kind of chromosomal abnormalities observed were; disturbances, stickiness, diagonals, chromosome breakage and c-metaphases. Also, a significant reduction in the percentage of abnormalities was observed. Biochemical studies included the analysis of M2 seed proteins using SDS-PAGE, isozyme analysis for both esterase and peroxidase and element analysis of Pb and N.