A battery cooling system for a vehicle may include an air conditioning device including a compressor, a condenser, an evaporator, and a first expansion valve connected through a refrigerant line and circulating a refrigerant to cool the internal of the vehicle; a cooler including an electric device radiator and a first water pump connected with a cooling line and circulating coolant to cool a motor and an electric device; a battery module in which the coolant circulated therein through an operation of a second water pump provided on a battery cooling line, connected with the cooling line through the battery cooling line; and a chiller connected with the refrigerant line through a connection line, provided on the battery cooling line, and controlling a temperature of the coolant by heat-exchanging the coolant and the refrigerant selectively introduced thereinto.