The time-dependent Schr?dinger equation of realistic hydrogen atom in intense laser field and static electric field is solved by split-operator method,and the abnormal behaviors of high-order harmonic generation(HHG)in intense laser field is investigated,which is caused by a static electric field. Our study indicates that intensity of odd-order harmonic generation decreases,even-order harmonic generation appears and the HHG spectrum exhibits a doubleplateau structure in the presence of a static electric field. By using wavelet transform,the emission of HHG in different time is obtained. And by means of semiclassical theory,the changes of HHG for realistic hydrogen atom in the static electric field is explained.