An exhaust gas sensor (100) is configured to detect an oxygen concentration or air-fuel ratio in exhaust gas of an internal combustion engine. The exhaust gas sensor includes a sensor element (10) and a glass coating film (20). The sensor element is configured to detect an oxygen concentration or air-fuel ratio in the exhaust gas sensor. The glass coating film (20) is formed on at least part of a surface of the sensor element and capable of absorbing a Mn component contained in the exhaust gas at 700° C. The internal combustion engine uses a fuel having a Mn concentration in excess of 20 ppm.