In view of the poor environmental adaptability,low accuracy and high cost of the non-contact shield tail gap measurement system,the research and development of the contact shield tail gap measurement device was carried out.The magnetic sensitive angle sensor was used to measure the angle,then the angle value was converted into a distance value through mathematical calculation,and the corresponding shield tail gap value was obtained,by which the real-time measurement of the shield tail gap was realized.The system was tested and applied on the project site and good application effects were achieved.The measuring device can realize continuous real-time measurement of the shield tail gap,the measurement data can be stored locally and read remotely,and the measurement efficiency is high.Mechanical measurement does not require complex data processing,and the measurement error is relatively small,which can be controlled within 1 mm.The cost of the mechanical shield tail gap measuring device is low,which can reach one-fifth of the non-contact construction cost.So the engineering cost can be effectively reduced.