This work presents an experimental study to enhance the thermal contact conductance of high performance thermal interface materials (TIMs) using gallium alloy. In this experiment, the gallium alloy-based TIMs are synthesized by a micro-oxidation reaction method, which consists of gallium oxides (Ga2O3) dispersed uniformly in gallium alloys. An experimental apparatus is designed to measure the thermal resistance across the gallium alloy-based TIMs under steady-state conditions. The existence of Ga2O3 can effectively improve the wettability of gallium alloys with other materials. For example, they have a better wettability with copper and anodic coloring 6063 aluminum-alloy without any extrusion between the interface layers. Gallium binary alloy-based TIMs (GBTIM) or ternary alloy based-TIMs (GTTIM) are found to increase the operational temperature range comparing with that of the conventional thermal greases. The measured highest thermal conductivity is as high as 19.2 Wm−1K−1 for GBTIM at room temperature. The wide operational temperature, better wettability, and higher thermal conductivity make gallium alloy-based TIMs promising for a wider application as TIMs in electronic packaging areas. The measured resistance is found to be as low as 2.2 mm2 KW−1 for GBTIM with a pressure of 0.05 MPa, which is much lower than that of the best commercialized thermal greases. In view of controlling pollution and raw materials wasting, the gallium alloy-based TIMs can be cleaned by 30% NaOH solution, and the pure gallium alloys are recycled, which can satisfy industrial production requirements effectively.