A body fat measurement device includes multiple electrodes, a trunk area width detection unit for measuring a trunk area width and a trunk area depth, a body impedance measurement unit that measures a body impedance of a body using the multiple electrodes, and a body fat mass calculation unit that calculates a body fat mass based on the measured body impedance and the trunk area width and trunk area depth. A frame-shaped fitting unit in which the trunk area width detection unit is provided and that is capable of being disposed so as to surround a measurement subjects trunk area can be mounted on and removed from a platform unit in which foot electrodes are provided, and is stored within the platform unit during a stored state.