On the basis of the function transformation,Grey system theory and the features of the arccosine and linear functions,a new transformation and a generalized GM (1,1) model are proposed.Then that the new transformation could improve the ratio of smoothness of the original statistical data is proved.And that this new transformation is a stepwise compressible transformation and may decrease the reduction error are also established.Regarding the simulation accuracy of the model,an example is given to illustrate that our generalized GM (1,1) based on the combination of the arcconsine function with ...