Aiming at the automatic modulation recognition of OFDM signal and single carrier modulation,a recognition method based on ITD and high order cumulants has been proposed in this paper.By decomposing the unknown signal using ITD,the instantaneous amplitude of the inherent rotating components is extracted. By analyzing the normalized fourth order cumulants features of the complex signal amplitude,modulation recognition of OFDM signal and single carrier signals is achieved,and modulation recognition of single carrier signals are also achieved by new feature parameters proposed. When SNR is not less than 5 dB,the simulation results on MATLAB indicate that identification probability of this proposed method is up to 99%.