A step motor positioning structure for a belt-type continuously variable transmission having a speed-change control valve for controlling a primary pressure to be supplied to a primary pulley, a servo link, and a step motor for driving, by way of the servo link, the speed-change control valve in response to a speed-change command signal is provided. The step motor positioning structure includes a motor bracket formed integral with the step motor and having an elongated hole and a circular hole, a bracket support supporting thereon the motor bracket, a first positioning member protruding outward from the bracket support and inserted in the elongated hole, and a second positioning member protruding outward from the motor support and inserted in the circular hole.