Potentiostatic electrolytic gas sensor

The purpose of the present invention is to provide a potentiostatic electrolytic gas sensor capable of detecting gas with a high degree of reliability. In a potentiostatic electrolytic gas sensor according to the present invention, a working electrode and counter electrode are provided inside a casing with an electrolytic solution therebetween. A working electrode lead member has one end that is drawn outside of the casing and another end that is electrically connected to the working electrode. A counter electrode lead member has one end that is drawn outside of the casing and another end that is electrically connected to the counter electrode. The potentiostatic electrolytic gas sensor is characterized in that the working electrode lead member, the counter electrode lead member, or both comprise a metal selected from gold, tungsten, niobium, and tantalum.