Abstract: In the oil, gas and other chemical industries, different degree of damages, such as corrosion, thinning and even perforation often appears on the tank bottom after a long time operation, which affects the safety of production. The artificial blocks simulating the tank edge were inspected by using high-frequency ultrasonic guided waves of mode S0, and influences on testing capacities of high-frequency ultrasonic guided waves in the different conditions were obtained. Based on the experiment, the tank edge plate was detected successfully by means of the large area and in-service rapid inspection, and the tank corrosion defects at the edge of the plate were found. Through artificial blocks contrast experiment and in-service inspection, it is concluded that the corrosion testing of tank edge floor by high-frequency guided waves is feasible.