The　simplified　analytical　method　can　quickly　estimate　the　internal　force　and　deformation　of　the　tunnel　structure　after　earthquakes,　and　it　is　widely　applied　in　the　preliminary　earthquake　resistance　design　of　tunnel.　Therefore,　the　applicability　analysis　of　simplified　analytical　methods　and　accuracy　improvement　are　significant　for　engineering.　In　this　paper,　the　axial　force　and　bending　moment　under　the　hydrostatic　stress　are　derived　by　improving　the　simplified　Bobet＇s　analytical　equation　for　internal　forces　of　circular　tunnels　under　compression　waves.　Combined　with　shear　stress　of　the　simplified　Bobet＇s　analytical　solution,　the　analytical　solution　for　the　axial　force　and　bending　moment　of　the　circular　tunnel　under　compression　waves　is　improved　in　this　study.　The　improved　simplified　analytical　formula　is　verified　by　the　near-field　fluctuation　finite　element　method,　the　impact　of　tunnel　depth　on　the　calculation　accuracy　of　the　improved　analytical　formula　is　studied　for　different　site　categories.　The　results　show　that:　(1)　the　new　analytical　solution　can　obviously　increase　the　prediction　accuracy　of　the　tunnel　bending　moment,　which　is　especially　suitable　for　tunnels　located　in　hard　rock.　(2)　When　the　buried　depth　of　tunnel　is　shallow,　the　prediction　error　of　axial　force　and　bending　moment　of　the　simplified　analytical　formula　is　large,　and　the　softer　the　site　soil　is,　the　larger　the　prediction　error　obtains.　When　the　buried　depth　is　more　about　8　m,　the　analytical　solution　ftis　well　with　the　numerical　results　under　five　groups　of　sites.　©　2020,　Science　Press.　All　right　reserved.