Worldindustrialization has made many bio-environmentalproblems including productionand releaseof significant amount oftoxinsandpollutantssuch asheavymetals(copper, lead, cadmium and arsenicc.). Nowadays, scientificassociations have warned of the adverse effects heavy metal toxicityonplants and their transfertohuman-beingsthroughfood chain. Thus, the introduction of a suitable method in order to re-uptake of heavy metalsfromsoilis essential. Bioremediationand using the potential of beneficialsoilmicroorganisms in establishing symbiotic relationshipwithplantsisan effective approach for reducing soil contamination of heavy metals. This study was conducted to investigate the effects of individual and simultaneous inoculation of three bacteria with different ability in sidrophore production ( Sinorizhobium Meliloti (47-3), Sinorizhobium Meliloti (27) and Pseudomonas fluorescent (p169)), and an endophytic fungus; Pirformospora indica on some morphological and physiological characteristics of alfalfa ( Mdicago sativa ) in response to different levels of Cadmium (0, 2, 5 and 10 mgCd/Kg). The experiment was conducted at greenhouses of agricultural college (Isfahan University of technology) by using the sterile sand-perlite (2: 1 v/v), in a completely randomized design with three replications. The results showedthat shoot and root dry weight, root nodulation, N concentration of shoot, ironandphosphorusconcentration inthe shootsandroot parts of plant and also photosynthesis of inoculated plants with each bacterium and P.indica under cadmium contamination were significantly(P 5%) lower than non-contamination conditions. Cadmium stress resulted in increaseing the shoot and root Cd concertrations and also the activity of some antioxidant enzymes such ascatalase antioxidant (CAT), ascorbateperoxidase (APX) andguaiacol peroxidase(GPX). Individual inoculation of studied bacteria in normal conditions (0 mg Cd /Kg) had greater positive effects on some parameters like root nodulation, shoot N concentrations, photosynthesis, root dry matter,ascorbate peroxidase and catalase peroxidase activitiesandFe concentration of the root in compare to dual inoculation of the bacteria and P.indica . However, under such conditions, P.indica inoculations alone or in combination with any of the studied bacteria resulted in significant increase of shoot and root P concentration and shoot Fe concentration compared with the other microbial treatment. Also this microbial treatment had a significant effect (P 5%) on shoot and root P concentration and shootdry weightatlevel of 2, 5and10mg Cd/Kg. Individualinoculation of bacteria at levels of 2and5mgCd/Kg had an improving effect on shoot and root dry weight, root nodulation. C0-inoculation of P.indica with each of the studied bacteriaat2, 5and10mg/Kg of cadmium, increased shoot and root dry weight, root nodulation and P concentration of shoot significantly. In addition, the mentioned treatment had asignificant positive effect on activity of catalaseand ascorbate peroxidase enzymes at level of 10mg/Kg cadmium. Individual inoculation of Sinorizhobium Meliloti (47-3) had the greatest effecton root absorption ofcadmiumand also the amount ofironin theshootandroot parts of plant.In general, due to positive effects of investigated microorganisms in this research on some physiological selection criteria like micronutrients uptake, shoot and root dry weights and antioxidant enzymes activities, they can be introduced as an effective biological approach in phytoremediation purposes. Keywords : Cadmium, phytoremediation , siderophores producing bacteria and Piriformospora indica