Corn　straw　was　used　to　prepare　activated　carbon　by　ZnCl2　activation　in　this　experiment.　Then　the　activated　carbon　was　used　to　adsorb　methylene　blue　dye　and　the　adsorption　kinetics　was　studied.　Langmuir　equations　and　Freundlich　equations　were　respectively　fitted　with　the　adsorption　isotherm.　The　results　indicated　that　the　adsorption　process　accorded　with　Langmuir　equation,　R2=0.9857.　The　adsorption　kinetics　equations　were　modeled　with　Pseudo-first-order　reaction　rate　equation,　Pseudo-second-order　reaction　rate　equation,　kinetic　equation　of　Bangham　and　kinetic　equation　of　Elovich.　Compared　with　other　equations,　Pseudo-second-order　reaction　rate　equation　could　more　clearly　describe　the　absorption　mechanism　in　methylene　blue　process　by　straw　activated　carbon,　R2=0.9979.　The　maximum　adsorption　capacity　achieved　909.09　mg/g.