Super high speed platform forwardlooking array radar faces the problem of strong clutter suppression. The clutter echo is not only rangedependent but also rangeambiguous, which results in severe performance degradation in moving target detection. To alleviate this problem, a range angleDoppler threedimensional adaptive processing approach based on frequency diverse arraymultiple input multiput output radar is proposed for range ambiguity clutter suppression. It is practical to reduce the dimensions of the processor by sum and difference beam in the transmitreceive spatial domains with adjacent Doppler channel in the temporal domain, which ensure the low complexity of the algorithm and enhance clutter suppression performance in the case of small number of samples. Simulation results demonstrate the effectiveness of the proposed method.