The accuracy and capacity planning issues of a pressure sensor parts were not up to the requirements in the machining process. Through analyzing the original processing, the main sources to low productivity and error were found, and the optimizations to the fixture and processing method were put forward. It is proved that the new processing technology is feasible, and the machining efficiency is improved by 67%, less cutting phenomenon is avoided, the qualification rate is up to 100%.It has some practical significance in similar parts machining.