As global competition intensifies and manufacturing industry demands for efficient production increase, how to shorten lead time while ensuring product quality becomes an important challenge for enterprises. Aiming at the key machining characteristics of the hole series of the marine diesel engine fuselage, this paper puts forward an optimized machining parameter scheme aiming at minimizing the machining time under the premise of ensuring the final machining quality. By analyzing the influence of machining parameters on machining time and combining the stable region of machining parameters, the optimization model of machining parameters is constructed, and the improved sparrow search algorithm is adopted to find the optimal combination of machining parameters in the stable region. The experimental results show that the optimization scheme can effectively shorten the processing time, reduce the delivery cycle, provide more economical and efficient processing solutions for enterprises, and promote the progress of manufacturing technology.