Because of the high correlation between the forward jamming and the radar transmitting waveform, it is easy to cause serious jamming to the radar after being received by the radar main lobe. In order to solve the main lobe interference problem, the forward interference signal model of OFDM-MIMO (orthogonal frequency division multiplexing-multiple input multiple output) radar main lobe was established, and the interference mechanism of OFDM-MIMO radar was analyzed. At the same time, based on the adaptive method processing theory, the analytical formula of OFDM-MIMO radar adaptive processing weight vector was derived, and an OFDM-MIMO radar forward main lobe interference adaptive suppression method based on range-dependent beam was proposed. Theoretical research and simulation results show that the proposed method can improve the output signal to interference plus noise ratio and effectively suppress the forward main lobe interference.