Provided is a mobile body configured to prevent a main body thereof from overturning in a case of being used in a state where an auxiliary wheel is not provided or the auxiliary wheel is not in contact with the ground. In a first control mode, by performing inverted pendulum control all the time, a posture of a main body portion (10) is maintained to be constant. For example, in the case where a user operates a changeover switch, a controller (21) shifts to a second control mode in which the rotation of main wheels (11) is driven and controlled so that an angle of the main body portion (10) with respect to the vertical direction becomes θ1′ which is greater than θ1. In the second control mode, the main wheels (11) and an auxiliary wheel (13) are in contact with the ground.
