A waterway switching device for a shower head includes a fixation portion, a switching mechanism, a driving mechanism, and an adjusting set rotatably disposed in the fixation portion. The fixation portion has an inlet waterway and at least two diversion waterways. The switching mechanism is assembled in the fixation portion and includes a water diversion plate, a first drive mechanism and a valve shaft. The water diversion plate can move with respect to the fixation portion, the valve shaft can slide with respect to the fixation portion, the first drive mechanism is connected to the water diversion plate and the valve shaft, the valve shaft sliding once drives the water diversion plate to rotate at a certain angle to switch and connect one diversion waterway to the inlet waterway. The driving mechanism includes-a rotation shaft and a second drive mechanism.