Abstract: As an important joint connection mode for fabricated concrete structure, the reliability of metal sleeve connection is the guarantee for the effective connection of fabricated component joints. In this paper, a method of sleeve grouting quality detection based on Time Domain Reflectance (TDR) testing principle is proposed. To verify the feasibility of this method, the sleeve grouting material contact tests with different grouting materials, different mix proportion and different contact state were designed. The TDR tester is used to collect the dielectric signals of the probe in the process of contacting the grouting material, and the typical function relationship between the moisture content and the dielectric signal is used to compare and analyze the collected signals. The change of dielectric characteristics of the probe in the process of contacting the sleeve grouting material was studied, and then the quality of sleeve grouting could be judged effectively. The results showed that the TDR method could effectively distinguish the contact state of the sleeve grouting material. There was a significant difference in the dielectric signal collected by the TDR tester before and after the probe contacting the grout. When the sleeve grouting material mix proportion was 12%, the three tests grouting material contact performance test changes were consistent, and the test effect was not strong when the mix proportion was 18% and 24%. In the process of testing the contact properties of grouting materials, the variation laws of volume water content and dielectric constant of grouting materials were similar, which could better distinguish whether the probe contacted the grouting materials. The test verifies the feasibility of using TDR method for sleeve grouting quality detection, and provides a new solution for the sleeve grouting quality detection of fabricated concrete structure.