A drug dispensing system includes at least one drug dispensing device including a plurality of dispensing modules for receiving and dispensing drugs, a plurality of installation blocks for allowing the dispensing modules to be mounted therein, and a controller for controlling dispensing of drugs from the dispensing modules, a plurality of drug refilling stations, a drug refilling unit for performing a drug refilling operation, a refilling authentication device for authenticating refilling information regarding the drugs refilled by the drug refilling unit, and a communication unit for transmitting authentication information regarding the first dispensing module confirmed by the refilling authentication device, a server for receiving the authentication information regarding the first dispensing module from the communication unit, and a database for storing the authentication information regarding the first dispensing module received from the server.
