Interfacial thermal resistance at solid-liquid interface is of great importance for thermal design of electronic devices. However, the quantitative investigation of interfacial thermal resistance is still open for question. In this study, the steady state method based on ASTM-5470 standard was applied to measure the interfacial thermal resistance at the microstructured Si-water interface. The effects of microstructure geometrical parameters on surface wettability and interfacial thermal resistance were studied. The experimental interfacial thermal resistance at the microstructured Siwater interface shows a dependence on the microstructure geometrical parameters, in correspondence with the surface wetting based on the intermediate wetting state theory.