Abstract: External agricultural inputs such as phosphorous are applied with the ultimate goal of maximising productivity and economic returns, while side effects on environment are often neglected. We have summarized the current understanding of environmental risk and assessment of agricultural phosphorus. The soil phosphorous mitigation, phosphorus levels, soil phosphorus sorption and desorption charactreristics, and the effects of P and manure application rate on phosphorus erosion and leaching losses were focused in this article. The methods of assessing environmental risk of agricultural phosphorus and P-index sound to assessing environmental risk of agricultural phosphorus were also reviewed. The advices on researching questions on environmental risk and assessment of agricultural phosphorus were directed.