A transmission for a lawn mower, for transmitting an output of a drive source to a driving wheel, the transmission including a speed-change transmission device and a power transmission device movably coupled to the speed-change transmission device. The power transmission device includes a first power transmission device coupled to the speed-change transmission device and a second power transmission device to which the driving wheel is coupled, and the first power transmission device and the second power transmission device are movably coupled to each other.