Nanocellulose　adsorbent　(AA/AM-g-NC)　from　cotton　linter　was　successfully　prepared　by　high　pressure　homogenization　with　the　assistance　of　an　ionic　liquid.　The　cotton　linter　was　first　swelled,　hydrolyzed　and　grafted　with　acrylic　acid　and　acrylamide　in　an　ionic　liquid　(1-butyl-3-methylimidazolium　hydrogen　sulfate　([Bmim]HSO4)),　and　then　further　treated　by　high　pressure　homogenization　and　finally　AA/AM-g-NC　was　obtained.　The　AA/AM-g-NC　adsorbent　was　characterized　and　used　as　adsorbent　to　adsorb　methylene　blue.　The　results　show　that　after　the　treatment　of　high　pressure　homogenization　assisted　with　hydrolysis　and　graft　in　ionic　liquid　AA/AM-g-NC　illustrated　as　crosslinked　net　with　fibril.　The　crystalline　of　AA/AM-g-NC　remained　as　cellulose　type,　with　a　little　increase　in　the　crystallinity.　The　appearance　of　functional　group　from　acrylic　acid　and　acrylamide　on　the　AA/AM-g-NC　surface　was　proved.　The　sorption　process　towards　methylene　blue　was　pH　value　dependent,　spontaneous,　exothermic　and　followed　the　Langmuir　adsorption　isotherm.　And　the　adsorption　kinetic　is　closer　to　the　quasi-second　order　kinetic　equation　and　controlled　by　both　intraparticle　diffusion　and　surface　diffusion.