Provided is a gas sensor element that can increase detection accuracy of a specific gas component concentration by means of a sensor cell by reflecting changes in the operating temperature of a gas sensor element. The gas sensor element is provided with a solid electrolyte body having oxygen ion conductivity, a heater stacked to the solid electrolyte body via a reference gas space, a pump cell adjusting oxygen concentration in a measuring gas space, a sensor cell detecting specific gas component concentration in the measuring gas space, and an electronic conduction detector cell detecting current resulting from electronic conduction due to the heater. The electronic conduction detector cell includes an electronic conductor electrode which is provided to a measuring gas side surface of the solid electrolyte body and covered with an insulator.