A switching mechanism for a video camera includes: a control unit; a driving device connected with and controlled by the control unit; a first belt pulley connected with the driving device; a second belt pulley smaller than the first belt pulley in diameter; a belt looped around the first and second belt pulleys for power transmission, and including a first protuberance; a translation member provided with a second protuberance so that through a loose fitting connection between the two protuberances, the translation member is driven to move; and a positioning element having a positioning plane, at least two inclines, and at least two top surfaces, wherein the positioning plane and the at least two inclines are designed to contact the second protuberance of the translation member alternately so as to restrict and reposition the translation member.