A gear (1) including: a hub (10) provided on an inner peripheral side and configured to be connected to a main shaft (8); a rim (14) provided on an outer peripheral side and formed with external teeth (12); and a gear web (16) connecting the hub (10) and the rim (14). The gear web (16) includes a first web (18) extending obliquely upward from the rim (14) to the hub (10); and a second web (20) extending obliquely downward from the rim (14) to the hub (10). The first web (18) includes a plurality of first web pieces (22) formed so as to be spaced apart in a circumferential direction, and the second web (20) includes a plurality of second web pieces (24) formed so as to be spaced apart in the circumferential direction. The first web pieces (20) and the second web pieces (24) are alternately arranged in the circumferential direction and are located at mutually different circumferential positions.