Abstract: Grey dynamic simulation on statistical corrosion rate data of tank is made by adopting modified grey dynamic model GM(1, 1) in grey system theory.Relative predictive equations are set up to forecast the corrosion rate of tank top, tank shell and bottom plate, Predictive accuracy is tested.Results show that predicted value is agreed well with the actual value, and the predictive equations have higher stability and accuracy.It is considered that the predictive equations can be used to forecast corrosion rate of tank in each part at future any time with less actual data, thus providing corrosion control and safety management of tank with scientific basis.