An air conditioner and a method for controlling the same include a compressor, a condenser, an evaporator, a receiver for storing at least one portion of a refrigerant passing through the condenser and a gas/liquid separator for filtering a liquid refrigerant of the refrigerant introduced from the receiver to supply a gaseous refrigerant into the compressor includes a first flow rate regulator for controlling the amount of refrigerant supplied into the receiver, a second flow rate regulator for controlling the amount of refrigerant introduced from the receiver into the gas/liquid separator, a first detection unit for detecting the amount of refrigerant stored in the receiver, and a control unit for controlling an opening degree of the first or second flow rate regulator, based on information of at least one of the amount of refrigerant detected by the first detection unit and the amount of refrigerant circulating in the air conditioner.