Electron　beam　irradiation　of　chloramphenicol　(CAP),　thiamphenicol　(THA)　and　florfenicol(FLR)　was　studied　by　using　aqueous　solution.　The　results　showed　that　the　degradation　of　THA　and　FLR　were　above　97%　when　the　doses　reached　at　10kGy.　When　the　dose　was　20　kGy,　the　degradation　of　CAP　was　above　98%.　The　higher　the　absorbed　dose　was,　the　better　the　removal　effect　was.　The　concentration　of　Cl-,　NO3-,　SO42-　and　F-　in　aqueous　solution　increased　during　irradiation　and　the　irradiated　solution　is　acidic.　The　main　radiolysis　products　were　determined　by　GC-MS　analysis　method,　and　the　degradation　pathway　was　studied.