An apparatus for controlling a hybrid vehicle, comprising: an engine; a motor-generator disposed in a drive system extending from the engine to a driving wheel for performing an engine start and a drive for the driving wheel according to a motor acceleration and a power generation according to a regeneration driven by the driving wheel; a mode switching device disposed in a linkage section between the engine and the motor-generator for switching between a hybrid vehicle mode, in which the hybrid vehicle is powered by both of the engine and the motor-generator, and an electric vehicle mode, in which the hybrid vehicle is powered by the motor-generator; and mode transition control means, characterized in that: said mode transition control means for implementing a delay time from a time at which an engine stop allowance condition is established to a time at which a mode transition from the hybrid vehicle mode to the electric vehicle mode is initiated in a high vehicle speed area that is higher than a delay time in another vehicle speed area, wherein the vehicle is traveling in the high speed area when it is traveling at or above a vehicle speed threshold level, wherein the mode transition control means sets a vehicle speed threshold value as a vehicle speed equal to or higher than a vehicle speed at which, in the electric vehicle mode, a constant speed run can be made, or as a vehicle speed equal to or higher than another vehicle speed at which a constant acceleration from the constant speed run can be made; wherein the high vehicle speed area is equal to or higher than the vehicle speed threshold value; and wherein the delay time is longer as the vehicle speed becomes higher in the high vehicle speed area. an engine; a motor-generator disposed in a drive system extending from the engine to a driving wheel for performing an engine start and a drive for the driving wheel according to a motor acceleration and a power generation according to a regeneration driven by the driving wheel; a mode switching device disposed in a linkage section between the engine and the motor-generator for switching between a hybrid vehicle mode, in which the hybrid vehicle is powered by both of the engine and the motor-generator, and an electric vehicle mode, in which the hybrid vehicle is powered by the motor-generator; and mode transition control means, said mode transition control means for implementing a delay time from a time at which an engine stop allowance condition is established to a time at which a mode transition from the hybrid vehicle mode to the electric vehicle mode is initiated in a high vehicle speed area that is higher than a delay time in another vehicle speed area, wherein the vehicle is traveling in the high speed area when it is traveling at or above a vehicle speed threshold level, wherein the mode transition control means sets a vehicle speed threshold value as a vehicle speed equal to or higher than a vehicle speed at which, in the electric vehicle mode, a constant speed run can be made, or as a vehicle speed equal to or higher than another vehicle speed at which a constant acceleration from the constant speed run can be made; wherein the high vehicle speed area is equal to or higher than the vehicle speed threshold value; and wherein the delay time is longer as the vehicle speed becomes higher in the high vehicle speed area.