For a range correction fuze of a rocket range-extended projectile, a DSP-based trajectory calculation and correction controller that is cooperated with MCU is designed to examine the axial acceleration during the flying of a projectile, and to perform the trajectory calculation and the start-up time calculation of a correction mechanism, and to control the action of a resistance-correction mechanism. When designing the hardware and the software, the tasks for DSP and MCU are reasonably assigned. The DSP mainly completes the collection of the acceleration data, the trajectory calculation and the start-up time calculation of the resistance-correction mechanism, while MCU mainly completes the time counting and controls the startup of the resistance-correction mechanism according to the time calculated by DSP. This device also can store the flying acceleration measurement data of the projectile, the trajectory calculation results, etc., which can be adopted as the basic data for analyzing the working correctness of the range correction fuse at the research stage. It is proved in the range test that this device can resist the high-impact overloading during the emission, and can normally complete the tasks such as the trajectory calculation and the resistance-correction mechanism startup control during the flying of the projectile.