A belt-type continuously variable transmission capable of continuously changing a speed reduction ratio of a driven pulley to a drive pulley, has a speed reduction ratio regulation mechanism that regulates a minimum speed reduction ratio of the driven pulley to the drive pulley. The driven pulley includes a fixed sheave, a movable sheave displaceable in an axial direction with respect to the fixed sheave, and a coil spring that urges the movable sheave toward the fixed sheave. The speed reduction ratio regulation mechanism has a swing arm that adjusts an allowable range in which moving away in an axial direction of the movable sheave with respect to the fixed sheave is possible, and a regulation drive section that drives the swing distal end portion of the swing arm to swing continuously.