A speed change gear comprising: a housing that supports an input shaft and an output shaft rotatably about a common input/output axis, and that has a plurality of internal gears (11, 12) having different inside diameters on its inner peripheral surface; and a plurality of change gear units (131, 132) that are respectively arranged at locations of the housing in a direction along the input/output axis, at which the plurality of internal gears (11, 12) are formed, that are respectively in mesh with the plurality of internal gears (11, 12), and that change the speed of rotation from the input shaft to the output shaft, wherein each of the change gear units (131, 132) includes a rotating member (240, 340) that is supported by the housing rotatably about the input/output axis, and that has one of a pin (41, 341) protruding in the direction along the input/output axis and an insertion hole (62, 72, 162, 172) in which the pin (41, 341) is inserted; an eccentric member (51, 52, 151, 152) that centers on an eccentric axis that is eccentric with respect to the input/output axis; and an annular oscillating member (60, 70, 160, 170) that is rotatably supported on an outer peripheral side of the eccentric member (51, 52, 151, 152), that has an external gear (61, 71, 161, 171) which is formed on an outer peripheral surface and which is able to be in mesh with the internal gear (11, 12) and the other one of the pin (41, 341) and the insertion hole (62, 72, 162, 172), and that oscillatingly rotates as the eccentric member (51, 52, 151, 152) rotates about the input/output axis, the plurality of change gear units (131, 132) include one side change gear unit and the other side change gear unit that are next to each other, the eccentric member (51, 52) of the one side change gear unit is coupled to one of the input shaft and the output shaft, the rotating member of the one side change gear unit is coupled to the eccentric member (151, 152) of the other side change gear unit, and the rotating member of the other side change gear unit is coupled to the other one of the input shaft and the output shaft, characterized in that an outer peripheral surface of the rotating member of the one side change gear unit is supported by the pin of the rotating member of the other side change gear unit. a housing that supports an input shaft and an output shaft rotatably about a common input/output axis, and that has a plurality of internal gears (11, 12) having different inside diameters on its inner peripheral surface; and a plurality of change gear units (131, 132) that are respectively arranged at locations of the housing in a direction along the input/output axis, at which the plurality of internal gears (11, 12) are formed, that are respectively in mesh with the plurality of internal gears (11, 12), and that change the speed of rotation from the input shaft to the output shaft, wherein each of the change gear units (131, 132) includes a rotating member (240, 340) that is supported by the housing rotatably about the input/output axis, and that has one of a pin (41, 341) protruding in the direction along the input/output axis and an insertion hole (62, 72, 162, 172) in which the pin (41, 341) is inserted; an eccentric member (51, 52, 151, 152) that centers on an eccentric axis that is eccentric with respect to the input/output axis; and an annular oscillating member (60, 70, 160, 170) that is rotatably supported on an outer peripheral side of the eccentric member (51, 52, 151, 152), that has an external gear (61, 71, 161, 171) which is formed on an outer peripheral surface and which is able to be in mesh with the internal gear (11, 12) and the other one of the pin (41, 341) and the insertion hole (62, 72, 162, 172), and that oscillatingly rotates as the eccentric member (51, 52, 151, 152) rotates about the input/output axis, the plurality of change gear units (131, 132) include one side change gear unit and the other side change gear unit that are next to each other, the eccentric member (51, 52) of the one side change gear unit is coupled to one of the input shaft and the output shaft, the rotating member of the one side change gear unit is coupled to the eccentric member (151, 152) of the other side change gear unit, and the rotating member of the other side change gear unit is coupled to the other one of the input shaft and the output shaft, characterized in that an outer peripheral surface of the rotating member of the one side change gear unit is supported by the pin of the rotating member of the other side change gear unit.