In this paper, we report the optimized combo sensor using quartz crystal resonator for analyzing the physicochemical properties of liquids. This sensor can measure the mechanical properties and the electrical properties simultaneously by integrating a LFE (Lateral Field Excited) sensor with an ACR (Antiparallel Coupled Resonator) or two types of ACR sensor on a same substrate. We optimized the electrode diameter of resonator for measuring a glucose aqueous solution or NaCl aqueous solution. Moreover, we measured concentration of glucose aqueous solution and NaCl aqueous solution with optimized sensor. This sensor is expected to be used for product quality control in industrial plants.