Abstract: A novel SDS based method for extracting Bt protein residues from the soil was developed based on studies on extraction conditions including concentration of SDS in the solution and temperature and duration of incubation.Results show that when SDS was 2 g·L^-1 in the solution at 50 ℃ for more than 4 hours it might extract effectively Bt protein residues from various types of soils,demonstrating better effect than the so-far known extraction methods,such as carbonate method,invertebrate gut fluid chemistry and PBST(phosphate buffer solution with Tween-20).