The present invention is a method of synchronizing files on a system including a client terminal, a management server, a test server and a production server, the method comprising the steps of: detecting, by an application installed on the client terminal, update of a file in a directory which the application manages; creating, by the application, an update history and difference information of the updated file; transmitting, by the application, the update history and the difference information to the management server; updating, by the management server, a file based on the update history and the difference information; transmitting, by the management server, the update history and the difference information to the test server; updating, by the test server, a file based on the update history and the difference information; displaying, by the test server, information of the updated file when a request to access the test server is transmitted by the client terminal; detecting, by the application, a request of deployment; transmitting, by the application, the request to the management server; detecting, by the management server, difference information between file management information of the test server and file management information of the production server; transmitting, by the management server, the detected difference information to the production server; updating, by the production server, a file based on the difference information; and displaying, by the production server, information of the updated file when a request to access the production server is transmitted by the client terminal;whereby the file of the production server is synchronized with the file of the client terminal.