A controller for a vehicle transmission in which a first transmission path including a first transmission mechanism that is able to continuously change its speed ratio and a second transmission path including a second transmission mechanism having a set speed ratio different from that of the first transmission mechanism are provided in parallel with each other between an input shaft to which torque is input from a driving force source of a vehicle and an output shaft that outputs torque to an output member, the vehicle transmission carrying out transmission of power between the input shaft and the output shaft via one of the first transmission path and the second transmission path, includes: performing means for carrying out a change shift for changing a path of the transmission of power between the first transmission path and the second transmission path by engaging a predetermined clutch mechanism; and setting means for setting a change speed ratio region that defines a range of a speed ratio of the first transmission mechanism such that a rotation speed difference between engagement members of the clutch mechanism, which are engaged with each other in carrying out the change shift, is smaller than or equal to a predetermined value. When a speed ratio outside the change speed ratio region is set in the first transmission mechanism, the change shift is not carried out.