To provide a shift switching device capable of simply forming a hydraulic oil supply passage to a hydraulic actuator in an AMT in which switching of a gear-change stage of an always-engaging-type gear transmission is performed by the hydraulic actuator.

In a shift rod for shifting a sleeve of a synchronized switching device, both end sections of the shift rod is supported by shaft support sections 50 and 60 at a case side, and a pair of hydraulic actuators are integrally formed on both end sections of the shift rod. The shift rod is a hollow shaft, and the hydraulic oil supply passages 32h and 32i to the pair of hydraulic actuators can be only arranged at one side shaft support section 50 side so that a hollow hole is prepared as an hydraulic oil passage to the other actuator. Therefore, the hydraulic oil supply passage to the actuators at a case side can be simplified.