With lumen-loading methods applied,the major influencing factors of loading degree in the process of magnetic paper were studied.The research results show that loading degree of soft wood is better than that of hard wood.The optimal loading conditions are:PEI dosage 5mg/g (on o.d.pulp),Al_2(SO_4)_3 concentration 0.0075g/l,the agitation speed 2500r/min,beating degree 29°SR,agitating time 30 min.The loading degree can be raised by increasing the dosage of Fe_3O_4and prolonging the treating time.