Long-term application of P containing fertilizers especially organic fertilizers usually increases the water soluble and soil available P content and at the same time may result in P accumulation in soil. Organic fertilizers also may enhance movement of P in the soil profile that could result in surface and ground water pollution. This study was conducted in Lavark experimental site on the field plots that received 3 rates (25, 50 and 100 ton/ha) of solid dairy manure, sewage sludge and urban solid waste compost, and one rate of chemical fertilizers (250 Kg/ha urea plus 250 Kg/ha mono-ammonium phosphate) for 1, 2, 3, 4 or 5 consecutive years to investigate the residual and cumulative effects of organic and chemical fertilizers on water soluble and bio-available P as well as P sorption index of the soil. The design of this experiment was split plot in a randomized complete block. Fertilizers were spread evenly on each plot and were incorporated into surface (0-30 cm) soil. Each treatment was replicated three times. Soil samples were taken from 0-30 cm depth of the plots, and analyzed for water soluble, bio-available P and P sorption index. Water soluble and bio-available P as well as organic matter content, calcium carbonate equivalent, pH and EC were determined in the soil samples. Average organic matter content of soil increased as the result of organic fertilizer application. The increase was proportional to the rate and was highest for diary manure and lowest for urban solid compost. Both water extractable and bio-available P contents of soil increased with the rate of application, the nature of organic fertilizer and the number (years) of applications, with the rate being the most effective and the nature of fertilizer the least effective. Dairy manure had the largest and solid waste compost the smallest positive impact on both water soluble and available P content of soil. Residual and cumulative effects of chemical fertilizer on water extractable and available P content of soil was generally higher than the effect of the lowest rate, but was much lower than medium or high rates of organic fertilizers. Effect of sewage sludge application on available P content of soil was greater than its effect on the water extractable P. Phosphorus sorption index was independent of the source of P (organic or chemical), the nature and the rate of organic fertilizers and was only significantly dependent on the number (years) of fertilizers' applications. Significant correlation between soil organic carbon and soluble P (r=0 .77***) and available P (r=0 .81***) were observed.