A battery module includes: a cell laminated body; a first and a second end plates which are provided at both end portions of the cell laminated body; and a sensor device which is mounted on a mounting surface and detects the voltage of each cell in the cell laminated body. The sensor device includes: a sensor device body; and a sensor fixing portion which is fixed to the first end plate by a fastening member. In the perpendicular direction, an end surface of the fastening member is located to be lower than or equal to an end surface of the sensor device body, the mounting surface of the cell laminated body is located to be lower than a bottom surface of the sensor fixing portion, and an end surface of the first end plate is located to be lower than the mounting surface of the cell laminated body.