This biological sample measuring device has a finger groove (6) provided in the short-side direction of a main body case (1) at a position that is closer to a sensor mounting portion (4) than a display section (5) on the rear side of the main body case (1). An interface unit (7) is provided on the front side portion of the main body case (1) corresponding to the finger groove (6). The interface unit (7) has an enter key (7b) and a plurality of cross keys (7ca), etc., disposed at a specific spacing around the outer periphery of the enter key (7b). The enter key (7b) is provided so that it protrudes farther than the cross keys (7ca), etc., on the front side of the main body case (1). A controller (13) performs a reset operation when a plurality of keys are pressed.
