An electrode module includes a working electrode, a counter electrode, a reference electrode and a well (container) for retaining an electrolytic solution and is used in electrochemical measuring instruments. This electrode module is produced by integrating the well with at least one of the working electrode, the counter electrode and the reference electrode. This integrated electrode includes a chip-like electrode having a thin membrane of an electrode material formed on the surface of a chip-like base metal. This chip-like electrode is disposed on and integrated with the bottom of the well in a detachable manner. There is provided the compact, low price electrode module of high repetition use efficiency with no need of maintenance and having easy handling.