To investigate the interlayer bonding performance of UHPC (steel-ultra-high performance concrete) under the action of shear free connection, different anti-corrosion and waterproof bonding materials were selected. By measuring the interlayer bonding strength and shear strength under different temperature and humidity environments, the optimal combination of bonding materials was selected using entropy weight-TOPSIS method. Simultaneously, SEM(scanning electron microscope) was used to conduct microscopic analysis of the failure interface under different combination conditions. The results show as follows. There is an optimal fit type for different combination structures. Polyurethane, as a waterproof bonding layer, has good bonding strength with different anti-corrosion materials. At 50 ℃, the bonding strength is greater than 9 MPa. As the degree of humidity increases, the bonding strength between epoxy resin and UHPC interface gradually decreases, while polyurethane and water-based epoxy resin show a trend of first increasing and then decreasing. Steel plate-waterborne organic anti-corrosion paint-waterborne epoxy resin-UHPC is the most suitable structure, with a shear strength greater than 5.65 MPa at 50 ℃; Moisture causes a decrease in the interfacial bonding strength between epoxy resin and polyurethane, while the fiber network structure formed by water-based epoxy resin binder enhances the interface connection with UHPC. The research results provide a reference for further optimizing the selection of steel UHPC interface bonding materials.