A hydraulic supply system for a hydraulically actuated automatic transmission, in particular for a belt-driven conical-pulley transmission. The system includes a primary pump driven by a primary drive system to provide pressure in a supply line connected to a regulating valve. The supply line is connected through a pilot valve to a control line in which a control valve is situated, with which the pressure that determines the setting of a transmission ratio adjusting valve is set. An auxiliary pump driven by an auxiliary drive system that is separate from the primary drive system includes an outlet line connected to the control line through a first valve that opens in the direction of the control line, and is connected to the supply line through a second valve that opens in the direction of the supply line.