A pot culture experiment was carried out and to the find out the effect of Rhizobium, Phosphobacteria and Root Nodule extract on the vegetative growth and biochemical changes in Black gram and Maize. The Black gram and Maize is vegetative parameters such as seed germination, shoot and root length, leaf fresh weight, leafs dry weight, shoot and root dry weight had analyzed and biochemical studies of both Black gram and Maize was carried such as total chlorophyll content, leave soluble protein and in vivo nitrate reductase activity. Among microbial inoculants, the Rhizobium + PB mixer was found most effective in terms of seed germination, shoot and root length, leaf fresh weight, leafs dry weight, shoot and root dry weight and also showed increase total chlorophyll content, soluble protein and nitrate activities in both Black gram and Maize.