Abstract: Atmospheric storage tank storage media are flammable, explosive, high toxic characteristic, and the leak, explosion and other accidents shall cause serious economic loss, personnel casualties and social influence. The existing inspection methods are subjected with undetected error, long construction period, the influence on production and error detection. High reliability and non-invasive overall evaluation might be realized by using the acoustic emission technique to on-line assessment of tank bottom corrosion status. The parameters filter, filter of the time difference sensor method, filtering noise, mechanical noise, electromagnetic noise interference data and the filtered data comprehensive rating according to the different levels of corrosion condition give the corresponding repair advice. Acoustic emission evaluation technology is characteristic of non-disrupting, needing no tank cleaning, reducing environmental pollution, saving tank inspection and maintenance costs, thus improving the management level of storage to be in safety condition etc.