In a control apparatus for a hydraulically operated vehicular transmission, the hydraulic pressure of a hydraulic clutch on the engaging side which is engaged at the time of speed changing (engaging pressure) is detected by a hydraulic pressure sensor. When the detected value of the engaging pressure has exceeded a predetermined value, the hydraulic pressure of a hydraulic clutch on the disengaging side to be disengaged at the time of speed changing (disengaging pressure) is reduced to a predetermined low pressure. Even if the detected value of the engaging pressure has exceeded a predetermined value YPC, the decrease in the disengaging pressure down to a predetermined low pressure QUPOFFB is delayed by a predetermined time YTMUP9 at the time of low oil temperature when the detected value of an oil temperature to be detected by an oil temperature sensor is below a predetermined value YTO. When a discrimination is made as to whether the detected value of the engaging pressure PC(N+1) has exceeded the predetermined value YPC from a predetermined time after the start of the speed changing, the time to start the discrimination may be delayed by a predetermined time at the time of low oil temperature.