PURPOSE: To restrain shocks upon gear shift by detecting the condition of engagement of a frictionally engaging element in accordance with the rotational speed of a turbine in a torque converter after the gear shift range is changed over into a travel range from a no travel range so as to regulate the hydraulic pressure.

CONSTITUTION: A range change-over means changes over the gear shift range of an automatic transmission into a travel range from a no travel range, and when this condition is detected by the range change-over means, a hydraulic control means feeds hydraulic pressure to frictionally engaging elements such as a clutch, a brake and the like, so that they are gradually shifted into their engagement conditions. In this phase, since the automobile is in a stop condition, the rotational speed of a turbine in a torque converter is lowered, and it comes to zero when the frictionally engaging elements fall in the engagement condition. Accordingly, the hydraulic control means sustains a relatively low hydraulic pressure until the turbine rotational speed detected by a detecting means comes to zero, and when it comes to zero, it is judged that the frictionally engaging element are engaged, and the hydraulic pressure is increased. Thus, it is possible to effectively prevent occurrence of shocks upon gear shift.