The　adsorption　and　separation　of　tungsten　and　molybdenum　are　important　for　efficient　recycling　of　W-Mo　resources,　which　requires　green　and　efficient　adsorbents.　In　this　paper,　Chitosan　(CS)-D301　material　was　obtained　by　impregnation　method　and　was　applied　to　adsorb　and　separate　W　and　Mo　in　solutions.　The　adsorption　optimization　results　indicated　that　W　was　adsorbed　by　CS-D301,　the　separation　factor　of　W/Mo　increased　to　26.45　compared　with　that　of　CS　21.34.　The　desorption　efficiency　was　still　above　94　%　after　five　adsorption-desorption　cycles.　FT-IR,　XPS　and　DFT　theoretical　calculations　indicated　that　the　surface　group　N+-R　of　CS-D301　showed　more　affinity　for　W,　making　it　easier　to　selectively　adsorb　W　over　Mo　than　CS　only.　N　was　the　surface-active　adsorption　site,　and　the　adsorption　process　belonged　to　chemical　adsorption　with　an　adsorption　energy　of　Eads　=　-957.64　kcal/mol.　CS-D301　was　expected　to　become　green　adsorbent　for　efficient　separation　of　W　and　Mo　to　support　resource　recovery,　protection　and　sustainable　development.