The　paper　analyses　the　deformation　and　the　force　condition　of　the　soil　nailing　wall　during　its　step-by-step　excavation.　The　universal　analysis　software　FLAC　for　geotechnical　engineering　and　the　numerical　stimulating　method　are　used　in　the　process　of　analysis.　Comparing　with　the　axial　force　calculation　result　of　CEC97:98　and　JGJ　120-99,　the　paper　tells　the　limitation　of　the　current　code　pointing　out　that　the　axial　force　of　soil　nailing　is　nor　only　associated　with　the　soil　pressure　of　the　controlled　soil　layer　but　mainly　correlated　with　the　increasing　of　the　trend　of　the　relative　displacement　between　soil　nailing　and　soil　which　is　because　of　the　accumulated　deformation　during　the　step-by-step　excavation　process.　The　paper　also　suggested　that　the　first　row　of　soil　nailing　should　be　lengthened　or　the　soil　property　should　be　improved　to　enhance　the　shoring　effect　and　to　intensify　the　joint　action　between　the　soil　layer　and　the　soil　nailing.