Abstract: In the orchanrds of 11,25,40,63years of the soil profile,with 0-20,20-40,40-60cm3levels of soil as test materials,the improved Bowman-Cole method was used,the change of soil organophosphorus with the age,soil layer and season were studied,in order to provide reference for the research of phosphorus cycle in orchards soil.The results showed that with the increase of orchards age,soil activity,medium activity,medium stability,high stability and total extraction of organophosphorus increased first and then decreased,with the lowest content in 11years orchard and the highest content in 25years orchard.With the deepening of soil depth,the activity and medium stability of soil organophosphorus decreased gradually,while the medium activity and high stability of soil organophosphorus and the total extracted organophosphorus decreased first and then increased.With the change of spring,summer and autumn,soil activity and high stable organophosphorus showed agradual decrease trend,medium activity first decreased and then increased,while medium stable organophosphorus and medium activity showed a trend of first increased and then decreased,and finally total extracted organophosphorus showed a trend of first decreased and then increased,but there was no significant difference between summer and autumn.Medium active organophosphorus was the main organophosphorus form in apple-pear orchards,followed by high stable organophosphorus form．