Space-time coding techniques are used to mitigate cross-correlation in the multiple-input multipleoutput radar. However, the imaging algorithms based on the conventional space-time coding schemes cannot accurately compensate the range-azimuth coupling, which limits the ability to handle the radar data acquired at high squint angles. To avoid the above drawback, a space-time coding scheme combined with ωK algorithm was proposed. In the space-time decoding processing, the modified decoding matrix and Stolt mapping operation were introduced to achieve the bulk focusing and differential focusing simultaneously, and the range-azimuth coupling could be accurately compensated. Theoretical analysis and simulation results show that the high quality imaging in the case of high squint angles can be achieved by the proposed scheme, and the cross-correlation interference can be canceled.