The ponderance of diffuse pollution in water environment has been attentioned to generally,and the diffuse pollution was already the active field for the research on the problem of water environment in the world.This paper started from the characteristics and the occuring mechanisms of agricultural diffuse pollution,and analyzed the interrelation between agricultural diffuse pollution and the water environment,discussed the influence of agricultural diffuse pollution on the water environment.The best management practices(BMPs) is applied broadly in the controlling of diffuse pollution.And the constructed wetlands,primary reservoirs,buffer and interlaced strip between water and land,soil and water conservation and agricultural eco-engineering are the main technologies for the controlling of agricultural diffuse pollution in research and applying relatively.