Abstract: Long-time integration is an effective method to improve weak radar target detection performance. However, the problems of across range unit (ARU) and across Doppler unit (ADU) of high-speed and maneuvering targets severely limits the integration performance. A new long-time hybrid integration approach is proposed in this paper. It divides the coherent process interval (CPI) into several sub apertures, and implements coherent integration in the same rang unit for each sub aperture. Subsequently, it implements non-coherent integration among several sub apertures with compensation of ADU effect. Furthermore, it applies a heuristics search strategy to reduce the huge computational complexity with increase of the motion order. Besides, it can decrease the signal-to-noise ratio losses efficiently by compensating high-order envelope shift of moving targets. Finally, some numerical experiments are provided to illustrate the detection performance improvement as well as the computational burden reduction of the proposed method.