The door lock key issuing system and method of accommodation using a smartphone is disclosed. Request for accommodation booking and payment of accommodation and which are issued to the door lock key information if the payment has been completed, using the door lock key information issued by performing the door lock and the Bluetooth communication of the accommodation configured to open the door the customer smartphone .; Receives requests for accommodation booking and payment from customers smartphone, customers door lock key information, the validity period is set to be operated for the accommodation reservation and when the agent payment and accommodation booking and payment is approved, pre-determined length of stay for this accommodation issued smart phones and door lock key issuing server to provide real-time information to the door lock key accommodation; Approved the accommodation booking and settlement by the door lock key issuing server, and receives a door lock key information from the door lock key issuing servers, smart phones when connecting to perform the authentication for smartphones and certified Smartphones and beultu Bluetooth Communication Door Locks the opening constitutes an accommodation for authenticating server. According to the door lock key issuing system and method of accommodation with the aforementioned smartphones, to receive issued the room door lock key information, reservations and customers to book your accommodation in a remote location in the smartphone configuration, whereby the check-in and check-out at the front desk without also there is an effect that it is possible to open and close the door of the room directly. There is no need for a door lock or return key information is very convenient.