A tire changing machine includes a base having a pedal-operated control system located on one side, a rotating platform which defines a surface upon which wheels of vehicles can be fixed, and which is supported by the base, a column rising from the base, an operating arm hinged to an upper area of the column, which can be oriented in a plane transverse to the column and parallel to the plane of the platform, between a work position facing the platform and an opposite rest position facing away from the platform and having a hinging end and an opposite end having a connection for a device holding work tools, a selector unit being interposed between the hinging end and the column, for selecting an orientation of the operating arm in its work position.