A method for preparing a carbonized resin DNA immunoadsorbent, which uses styrene, acrylonitrile, divinylbenzene, toluene, liquid paraffin, benzoyl peroxide and water solution of polyvinyl alcohol as raw materials, produces a DNA immunoadsorbent with 0.3-0.5 mg DNA per milliliter of resin using two-staged procedures for preparation of first carbonized resin, and secondly carbonized resin DNA immunoadsorbent. The resultant immunoadsorbent is high in adsorbent capacity, low in production cost, and can be synthesized without pyrogens. It therefore satisfies the demands of medical application for the treatment of systemic lupus erythematosus by immunoadsorption.