To provide a speed change gear which obtains a high gar ratio simply, improves transmission efficiency, and can be miniaturized by simplifying its structure.

The speed change gear 1 includes a housing 10 on which internal gears 11 are formed and a plurality of change gear units 31, 32 which are provided continuously in the direction of an input/output axis Lo, and are in mesh with the same internal gears 11 to change the speed of rotation from an input shaft to an output shaft. Each of the change gear units 31, 32 includes a rotating member 40 which has one of pins 41 protruding in the direction of the input/output axis Lo and insertion holes 62, an eccentric member 51 which centers on an eccentric axis La that is eccentric with respect to the input/output axis Lo, and an oscillating member 60 which oscillatingly rotates as the eccentric member 51 rotates about the input/output axis Lo.