PURPOSE: To correctly set and keep a speed ratio between drive and driven pulley assemblies by arranging a geared control system in a flat belt continuously variable transmission.

CONSTITUTION: A first sun gear 53 of a planetary gear system disposed between an inner guide passage discs 21, 22 and an outer guide passage discs 19, 23 is connected to the inner guide passage discs 21, 22, and their sun gears 53, 54 are provided in parallel in an axial direction. A set of a planetary gear 55 to be engaged with one sun gear 53, 54 is installed on a rotatable planetary carrier 51, and a set of a star gear 56 to be engaged with the other sun gear 54, 53 is supported at an angularly fixed position to the other sun gear. An inner circular gear 59 to be engaged with the planetary gear 55 and the star gear 56 is provided, and an angle changing means to selectively change angular relation between the planetary carrier 51 and the star gear 56 is provided.