Abstract: This paper mainly discusses miniature isolated solid-state encapsulation technology of high-temperature polysilicon pressure sensor, including static electricity bonding,stainless steel diaphragm selection and rippled design,laser welding,silicon oil infilling, isolation and other technologies used in sensor packaging. By adopting stainless steel diaphragm and high-temperature silicon oil as isolation materials, not only the encapsulation diameter of sensor is as small as 15 mm and under 1 mA drive,its full range output is 72 mV and zero stability is 0.48% F.S/mon,but also the reliability of the sensor is improved and its application is widely broadened.