Abstarct: Phosphorus is an important plant nutrient which is added to the soil as fertilizer. The high cost of production of chemical fertilizers and sediment rapidly in calcareous soils has led researchers to propose a method for dissolution or increase the availability of phosphorus fertilizers are renewed. One of the methods to increase availability of soil phosphorus, is the use of phosphate solubilizing microorganisms. To investigate the effect of Aspergillus Niger on soil phosphorus availability, an experiment in a completely randomized design with three replications was conducted in two stages of incubation and greenhouse. The treatments consisted of control, Aspergillus Niger, Sucrose, Alfalfa powder , Rock phosphate, Citric acid, Aspergillus Niger + Sucrose, Aspergillus Niger + Alfalfa powder, Aspergillus Niger + Rock phosphate, Aspergillus Niger + Rock phosphate + Sucrose, Aspergillus Niger + Rock phosphate + Alfalfa powder, Citric acid + Rock phosphate, Aspergillus Niger + Sucrose + Nitrogen, Aspergillus Niger + Sucrose + Nitrogen + Rock phosphate. The Incubation results showed that all treatments had a significant effect on the measured parameters. soil pH decrease over time with the use of treatments and electrical conductivity, soluble phosphorus, Olsen- extractable phosphorus soil has increased, the rate of change varied over time so that, over time, depending on the type of treatment to a greater extent than period of previous decrease or increased. The greenhouse results showed that by applying Aspergillus Niger soluble phosphorus 38/43 and phosphorus concentration 92/14 percent compared to the control. Application of both Aspergillus Niger, Alfalfa powder and rock phosphate enhanced available and soluble phosphorus, stem height, Shoot dry weight, root dry weight and phosphorus plants. According to the results, it seems the application of bio-fertilizers in addition to decrease the chemical fertilizers use, can help to conserve the environment, , reduce the soil contamination and act in production of better and desirable products.