A group of molecules extracted from the labial palpus of fly was reconstituted into plannar bilayer membranes and liposomes to construct the taste sensors. The existence of sodium ion channel in the extract of the labial palpus of fly was recognized by the plannar bilayer membrane experiment. Fluorescent dye, Di-8-ANEPPS, which is very sensitive to the change to the membrane potential, was used to clarify the availability of this system for sensor applications. The fluorescence intensity of liposomes was proportional to the concentration of salt solution (membrane potential) added as stimulative substances. Addition of tetrodotoxin (sodium channel blocker) revealed that sodium ion channel in the extract of the labial palpus of fly was successfully reconstituted into liposome.