Abstract: Tunnel arches are often prone to defects such as voids and voids. In order to accurately determine whether the secondary lining reinforcement of the tunnel was compliant, whether there were obvious defects inside the tunnel lining, and whether the tunnel concrete thickness and steel arch met conventional requirements, the application of ground penetrating radar technology in nondestructive testing of tunnel lining quality was studied. A differentiated electrical signal detection and conversion structure were designed, time depth sample values and real detection result sample values were used, combined with distance triggering and time triggering strategies, to maximize the control of radar antenna movement rate, maintain uniform speed forward, arrange nondestructive testing measuring lines and time points, match the optimal SIR-4000 geological radar reflection coefficient value, clarify more accurate positioning mileage, and output nondestructive testing results of geological radar tunnel lining. The application results of the example showed that this technology could accurately display the diseased areas and stress changes of tunnel lining, which conformed to the dynamic laws of the construction process. It had applicability and practical application, providing assistance for the efficient construction of tunnel engineering.