A correction support device (10) is worn on the upper body of a subject and supports the correction of the posture of the subject. A control circuit (22) calculates a differential (ΔAGL) representing the angle of inclination of the upper body of the subject on the basis of the output of an acceleration sensor (20) and compares the calculated differential (ΔAGL) with error angle conditions. The control circuit (22) also measures, on the basis of the results of the comparison, the duration of time during which the error angle conditions are continuously satisfied, and outputs a preliminary alarm (ALM1) or a principal alarm (ALM2) by driving a buzzer (16) when the measured duration of time reaches a reference value (REF1) or (REF2).
