Abstract: Recent years,we dedicated to the development of capacitance diaphragm gauge based on MEMS technology for the miniaturization of vacuum measuring instruments.Firstly,a differential pressure structure was made to verify the performance of the pressure-sensing diaphragm;then the absolute pressure structure was developed;finally,a prototype was constructed.At present,the development and performance test of the prototype have been completed.The experimental results show that the measurement range is 0.2 to 10³Pa,the resolution is 0.1 Pa,and the full scale accuracy is 0.1%.In the development process,we divided all the research work into several key technologies,including “preparation of flat pressure sensing diaphragm with large width-thickness ratio” “non evaporating getter film” and “sensor packaging”.This paper introduced the key technologies encountered and solved in the development process,and made expectations for future work.