Mobility, bioavailability and the environmental risk of heavy metals is associated with the changes in their chemical form in soils. Root induced changes affect distribution of heavy metals in various geochemical fractions and bioavailability of heavy metals in soil. Therefore, it is necessary to get more information about behavior the chemical forms of heavy metals in soil and their relationship with plants. Because few studies about the processes involved the heavy metals in the rhizosphere, especially in the hyper accumulatore plants, complicated relationship of heavy metals with plants, soil and microorganisms in the rhizosphere is not well known and understanding these processes can provide us the useful information for refining heavy metals contaminated soils, and disposal of they risk. The aim of this study was assessing the changes of soil chemical properties and chemical forms and bioavailability of Lead, Zinc, Copper and Nikel by distance from root of corn and canola in single and mixed culture system and the effect of green manure on this changes and survey efficiency of phytoremediation potential of corn and canola in single and mixed culture system. Therefore, the rhizobox system was used and inside each box using nylon mesh plates with holes of 45 micron, was divided into four zones. The plants, were planted in the middle zone. At the end of the growing season, roots and shoots of plants was isolated and soil were taken from each area separately. In order to determine the chemical forms of heavy metals, sequential extraction method was used. The results of the soil analysis showed that green manure and plant cultivation impressed soil chemical properties and chemical forms of heavy metals and also affected the efficiency of phytoremediation. Exchangeable form of Zinc on the rhizosphere and bulk soil was more than two middle zones. Exchangeable fraction of lead and copper and the associated organic matter fraction of copper, in rhizosphere was more than bulk soil. Related to organic matter and carbonate fraction of copper and bioavailability of nickel decreased with distance from the root by the regular process. While the bioavailability of zinc increased with distance from the root. The associated organic mater fraction of zinc and nickel and bioavailability of lead was highest in the near soil mass and was and lowest in the soil mass. The associated organic matter fraction of Lead and nickel in the rhizosphere was more than bulk soil. The carbonate fraction of lead and nickel in the near ??rhizosphere zone was more than mass soil. Oxide fraction of lead, zinc and nickel in the rhizosphere was more than bulk soil. Also the results of the plants analysis showed that green manure reduced the root yield and increased the shoot yield. Yield in mixed culture was more than single culture. Phytoextraction of zinc and nickel using intercropping corn and canola and single culture of canola was more than single culture of corn. While the phytoextraction of copper in corn mixed and single culture was more than canola. Green manure increased the phytoextraction of zinc but decreased the phytoextraction of copper. Therefore, the mixed and single culture has differential effects on soil chemical properties and distribution of heavy metals in different geochemical fractions. Using corn and canola for remediation of heavy metals from contaminated soils were useful. Mixed culture and use of green manure was effective to remediation of soils. Keywords: Bioavailibility, Rhizibox, Sequential extraction, Mixed culture, Canola, Lead, Zinc