The Multiple-Input Multiple-Output (MIMO) radar imaging with OFD-LEM has an important and practical value for non-cooperative moving targets detection and recognition. Some researches on the problem about moving target high-resolution range profile (HRRP) synthesizing method for MIMO radar with OFD-LFM signal are carried out in this paper. First of all, the imaging geometric figure of MIMO high-resolution radar with OFD-LFM signal is established. On the basis of that, a new moving target HRRP synthesizing method based on phase compensation for MIMO radar with OFD-LFM signal is proposed via strictly theoretical deduction and detailed principle demonstration. The moving target HRRP can be synthesized effectively by using the proposed method, because the orthogonality among the different sub-pulses is utilized. What's more, the condition of unwrapped HRRP is also obtained successfully. The simulation results validate the effectiveness of the proposed method.