Abstract: Some researches about spinning micro-Doppler signature of ballistic missile are carried out in this paper. Firstly, the format of spinning micro-Doppler signature of ballistic missile on the spectrogram with orthogonal frequency division linear frequency modulation (OFD-LFM) signal is analyzed in details via a strict theoretical deduction, and some related conclusions are obtained. Furthermore, a new micro-Doppler spectrogram synthesizing method with sparse frequency OFD-LFM signal is presented based on compressed sensing. By using the method, the spinning micro-Doppler signature curve can be reconstructed exactly and the side-lobe can be restrained on condition that the sub-frequency number in OFD-LFM signal is reduced apparently. Simulation results show the correctness of theoretical derivation and the effectiveness of the reconstructed method.