Considering the service life and operation safety of the tunnel structure, it is necessary to carry out research on the development of tunnel service safety monitoring and early warning system, explore the actual working state of the tunnel in real time, effectively monitor the disease of the tunnel structure and warn in time.In this paper, the design of tunnel service safety monitoring and early warning system is discussed and studied based on the comprehensive consideration of how to obtain the disease characteristics, spatial location, mechanical properties and related dynamic changes of the key parts of the tunnel in real time, aiming at the diseases such as water leakage and deformation in the regular detection of the tunnel during the operation period. A tunnel service safety monitoring and early warning system based on multi-sensor is recommended, which can provide a favorable technical reference for the applicability and rationality design of tunnel service safety monitoring and early warning system.