Compared　with　conventional　activated　sludge　system,　applied　magnetic　field　or　adding　magnetic　materials　in　activated　sludge　system　exhibits　a　better　performance　of　enzyme　activity,　sludge　settling,　microbial　activity.　It　also　shows　an　obvious　influence　on　bacterial　activity,　dissolved　oxygen　and　pollution　loadings.　Even　more,　the　removal　efficiency　of　organic　pollutions,　N　and　P　in　this　system　shows　an　obvious　increase.　The　biomagnetic　effect　is　a　promising　technology　in　wastewater　treatment.