A control apparatus for a vehicular drive system is provided. In the vehicular drive system having a power source portion connected with an input shaft of a step transmission portion in a manner capable of transmitting power, during sliding downshifting, even though the temperature of lubricant of the step transmission portion is a low temperature, the transmission impact can be suppressed. Duringsliding downshifting, an AT input shaft torque Ti applied to an intermediate transmission part (30) of the step transmission portion (20) in a low temperature Toil of the lubricant is comparatively larger than that in a high temperature of the lubricant. Therefore, even when the temperature Toil of the lubricant is the low temperature, an AT drag torque Tloss of the step transmission portion (20)is increased, and the transmission can be correspondingly developed when the temperature Toil of the lubricant is high. In this way, even though the temperature Toil of the lubricant is the low temperature, stagnation and regression of transmission can be suppressed, the transmission impact caused by increase of the drag loss of the step transmission portion (20) can be suppressed, and the driving performance is enhanced.