Pipeline intrusion and damage will cause serious environmental pollution and significant property losses. Pipeline damage positioning technology based on acoustic technology has become a trend in technological development. This paper proposes a MEMS acoustic sensor based on PMUT, which achieves acoustic impedance matching and high-reliability packaging through Alumina-Epoxy Resin filling. Two MEMS acoustic sensors are installed in the pipeline intrusion positioning detection system, and the pipeline is knocked to simulate the intrusion scene, and then the acoustic signal propagated in the pipeline is collected and analyzed. The results show that the propagation speed of the acoustic signal in the pipeline is 2 449 m/s, and the relative positioning error of the pipeline intrusion positioning detection method based on acoustic signals is less than 2%, which proves the feasibility of MEMS acoustic sensors for pipeline intrusion positioning monitoring.