As the increasing depth of the pipeline, the above ground marker system based on sound detection principle becomes the trend of pipeline technology. A new MEMS bionic acoustic vector sensor which has advantages of high sensitivity, high signal to noise ratio and high resolution has been put forward to use in the above ground marker systems. Different simulated comparing experiments have been done among the new type sensor, vibration sensor of piezoelectric ceramic and high sensitivity moving coil geo phone. The results show that MEMS bionic acoustic vector sensor has advantages of long detection distance, high reliability and low requirement of soil environment and so on. Thus the feasibility of MEMS bionic vector sensor in measurement on weak signal direction and its good prospects in location internal inspector can be verified.