An engine start control device includes a mechanical pump supplying hydraulic pressure; an electric pump connected in parallel to the mechanical pump and independently driven; a device for stopping the engine when an idling stop condition is satisfied and starting the engine when a restart condition and a fuel injection condition are satisfied; a device for driving the electric pump when the hydraulic pressure is less than a first hydraulic pressure when the engine is stopped by idling stop; and a device for driving a motor at a target speed and for performing control so that the change in the target speed is small compared with the change exhibited when the hydraulic pressure is equal or higher than a second hydraulic pressure, when the hydraulic pressure is less than the second hydraulic pressure, and the restart condition is satisfied after the idling stop.