A transmission includes a gear shift set including a shift gear and a switching mechanism, and another gear shift set including a shift gear and a switching mechanism. At a side face of the lower shift gear, dogs are provided to protrude. The switching mechanism includes a first ring configured to rotate integrally with a shaft, a second ring configured to rotate integrally with the first ring, and an elastic member connecting the first ring and the second ring. The first ring includes first projection portions, and a first abutment portion allowing a shift member to abut thereon. The second ring includes second projection portions, and a second abutment portion allowing the shift member to abut thereon.