Abstract: Silicon piezoresistive pressure sensors are widely used in various industries due to their high stability and precision. However, with the continuous expansion of application fields, various failure problems inevitably occur. This paper takes the common output anomaly failure mode as an example, conducts systematic failure mechanism analysis on the sensor, and adopts effective preventive measures to reduce the probability of occurrence. The analysis content can provide systematic analytical approaches for sensor failure analysis, thereby improving the reliability during sensor operation.