In　order　to　solve　the　difficult　problems　of　agricultural　information　retrieve　and　improve　the　efficiency　of　intelligent　retrieve,　the　paper　studied　the　application　of　ontology,　introduced　principles　of　ontology　construction　and　ontology　process,　then　developed　the　retrieve　system　with　the　help　of　intelligent　searching　technology,　which　can　be　integrated　with　the　traditional　retrieve　systems,　greatly　improving　the　semantic　support　and　performance　of　retrieve　system,　developing　the　implicit　knowledge　in　the　mind　of　the　users,　standardizing　and　improving　the　information　demand　of　the　user.　The　practice　has　proved　that　the　ontology　technology　in　the　agricultural　information　greatly　promotes　the　accuracy　and　reliability　of　the　agricultural　information　retrieve.