Abstract: Studies have been made of the technical features of detection methods regarding acoustic emission, magnetic flux leakage and magnetic particle. Tests were carried out for the bottoms of diesel oil tanks in different corrosion according to the engineering requirement. Recommendations on the integrity evaluation of storage tank bottom were given based on the relationship of three detection methods of acoustic emission, magnetic flux leakage and magnetic powder, which was believed to be able to enhance the development foundation of safety detection in storage tank.