Taking　the　reaction　of　the　radiation　to　the　spacetime　into　consideration,　we　discuss　Hawking　radiation　spectrum　and　Bekenstein-Hawking　entropy　correction　in　Friedmann-Robertson-Walker　(FRW)　universe　by　the　analytical　continuation　method.　We　derive　the　radiation　spectrum　that　satisfies　the　unitary　principle　and　the　logarithmic　correction　term　of　entropy　in　FRW　universe.