Abstract: By adsorption method,adsorption character and mechanism of Cu²⁺ by celery residue were studied.The results showed that with the smaller size of celery residue,Cu²⁺ adsorption rate increases.Under the same Cu²⁺ initial concentration,with the addition of more celery residue,Cu²⁺ adsorption rate increases.Under the same addition amount of celery residue,Cu²⁺ adsorption rate all has once maximum value,as initial concentration is 15 mg/L.Orthogonal tests showed that the optimum adsorption conditions are the wastewater pH=6,temperature 30℃ and soaking time 3 h,and influence degree for 3 factors from big to small is pH,temperature and soaking time.Single molecule layer absorption dominant is Cu²⁺ adsorption,and adsorption isotherm is fit to Freundlich adsorption isotherm.Under standard condition,the adsorption heat for celery residue on Cu²⁺ is 10.49 kJ/mol.The adsorption rate for celery residue to Cu²⁺ is quick first,and then become slow after more than 60 min.First kinetic model can describe the adsorption kinetics of celery residue more better.