Nitrogen potassium and phosphorus are vital macronutrients for plant growth. Nitrogen in the soil can be lost due to denitrification, leaching, and volatilization. Rock phosphate is the only phosphate source in the world which is being depleted. When it is applied to soil, phosphate and potassium were quickly immobilized and cannot be absorbed by the plants. In this experiment total 8 free living N2 fixing bacterial isolates were isolated from different soil samples. Among the all isolates, isolate NP-2 and NP-7 produced more than 600 µg/ml ammonia. The isolated microorganisms 16s rRNA gene sequence was showed 99.9% similarity with Azotobacter vinelandii. The four soils showed clear difference in PSB bacterial diversity, virgin soil had completely 81 colonies and 16 different isolates in that isolate B7 and B6 were in highly prevailed. Plants were treated with different isolated organisms and growth parameters were evaluated in rice plants.