The invention relates to a tyre demounting mechanism for tyre detection, in particular to a tyre demounting mechanism, and solves the problems that an existing tyre demounting mechanism for tyre detection is large in occupied space and complicated in operation. A rolling shaft is mounted on a roller through two first deep groove ball bearings; a push rod of an electric push cylinder is positioned between two horizontal linear guide rails, and the push rod and the two horizontal linear guide rails are arranged in parallel; a second bearing cover is fixed to a bearing mounting seat through bolts; a paw unit is connected to a fixed plate through bolts; a rotor seat is fixedly mounted on a sliding block through a nut; the sliding block is mounted on a base through a linear guide rail bearing; a stepping motor is fixed to the upper part of the base through a motor mounting seat, and an output shaft of the stepping motor is fixedly connected to the upper end of a screw rod through a coupling; the lower end of the screw rod is mounted at the lower part of the base through a forward deep groove ball bearing and a backward deep groove ball bearing; and the lower end of the base is in bolt connection with a linear module connecting plate, and a unit sliding block is mounted on a vertical guide rail through a ball linear bearing. The tyre demounting mechanism disclosed by the invention is used for tyre detection.