A　new　nitrogen　doped　sinocalamus　oldhami　lignin-based　activated　biochar　(denoted　as　N-BGAC)　with　a　notably　high　adsorption　efficiency　was　prepared　for　the　removal　of　malachite　green　(MG).　The　properties　and　structure　of　N-BGAC　were　thoroughly　characterized,　alongside　an　investigation　into　the　MG　adsorption　process.　The　findings　revealed　that　N-BGAC　possessed　a　substantial　specific　surface　area　of　2238　m(2)　g(-1),　nearly　double　that　of　the　activated　biochar　lacking　nitrogen　doping　(BGAC).　Additionally,　N-BGAC　exhibited　exceptional　adsorption　efficiency　for　MG,　boasting　a　maximum　adsorption　capacity　of　1372.5　mg　g(-1),　marking　an　enhancement　of　nearly　2.5　times　compared　to　BGAC.　By　exploring　the　adsorption　mechanism,　it　could　be　found　that　the　adsorption　process　was　a　spontaneous　exothermic　reaction,　and　mainly　controlled　by　pore-filling　effect,　electrostatic　interactions,　hydrogen　bonding,　hydrophobic　interactions　and　pi-pi　bonding　interactions.　Crucially,　in　the　regeneration　experiments,　the　removal　percentage　of　MG　could　still　reach　81.5%　after　four　cycles　of　regeneration,　making　it　promising　in　the　contaminant　removal.