The consumption of P fertilizer has been increasing dramatically in China and so has the content of available P in the soil since the 1980's.However, how the change will affect production and application of P fertilizer in China remains to be unclear and a concern related to food safety and environment safety.Relationship between P balance and change in soil Olsen-P in eight different types of arable soils were evaluated.Results show that on average, about 3.1% of the annual P surplus in the arable land in China was considered as Olsen-P.In the period from 1980 to 2003, the cumulative P surplus reached about 392 kg hm^-2, from which it can be inferred that currently the content of Olsen-P in the arable land of China is about 19 mg kg^-1.If soil available phosphorus is to be increased to and maintained around 40 mg kg^-1 in the future thirty years, the demand for phosphorus fertilizer will rise to 12.5 million tons in 2020 and then drop to 10.5 million tons in 2035.