Abstract: In a hydraulic control system for an automatic transmission comprising a hydraulic servomotor C-2 for a clutch or brake adapted to engage and disengage necessary rotary components of a planetary gear mechanism, and a select valve for selectively supplying hydraulic pressure to the hydraulic servomotor C-2 dependent on two transmission states, the select valve has two input ports selectively supplied with hydraulic pressure dependent on the two transmission states and one output port for outputting hydraulic pressure to the hydraulic servomotor C-2, a first orifice is disposed between the output port and the hydraulic servomotor C-2, and a second orifice is disposed on the same side as either of the two input ports.Upon an upshift from the 2nd to the 3rd speed in the D range condition, a shift valve is changed over such that the line pressure is supplied to one input port of the select valve via a line pressure output port and the second orifice to move a ball valve body in the select valve.