A control apparatus for a vehicular power transmitting system including (a) an electrically controlled differential portion which has a differential mechanism and a first electric motor connected to a rotary element of the differential mechanism and which is operable to control a differential state between rotating speeds of its input and output shafts by controlling an operating state of the first electric motor, and (b) a step-variable transmission portion which constitutes a part of a power transmitting path between the electrically controlled differential portion and a drive wheel of a vehicle, the control apparatus including a coasting-shift-down control portion configured to implement a coasting shift-down action of the step-variable transmission portion during a coasting run of the vehicle, only when a parameter correlating with a shaft torque of the step-variable transmission portion during the coasting run is held within a predetermined range.