A seat load measuring apparatus which can be effectively adopted to various kinds of motor vehicles without requiring various load sensors having cables of different lengths according to the kinds of motor vehicles, thereby providing improved installation, maintenance and manufacturing benefits. A seat load measuring apparatus may include a connector of a load sensor is a male connector having terminals projecting downwardly. The entry of the male connector faces the open bottom of a protector. On the other hand, a cable to be connected to an ECU is provided with a cable-side connector. The cable-side connector is composed of a female connector which is detachable relative to the male connector. Therefore, the load sensor and the cable are detachable from each other, thereby achieving the adaptability of the load sensor and the connector casing a relative to various kinds of motor vehicles.