This paper has analyzed the calibration model of the storage tank in detail. There are two important pa- rameters that Influence oihank calibration, and they are angle of Inclination α and deflection angleβ respectively. Because of the oil tank defleetion that often happens , The displacement recognition is the key to correcting calibra- tion. First, this paper makes general introduction for the PSO algorithm. By the data that has been provided, It cal- culates the specific value of the angle of Inclination α and deflection angleβ by using PSO algorithm. Tests s...