Disclosed is a composite service control system resolving a conflict, the system including a conflict set defining unit to classify and define an explicit conflict set and an implicit conflict set, a determining unit to determine an application triggering condition of a new application, and to determine whether an intersection between an explicit conflict set and an explicit conflict set exists and whether an intersection between an implicit conflict set and an implicit conflict set exists, an application managing unit to transmit the application triggering condition and execution information of the existing application and to request a defining of a conflict resolution policy or a changed application triggering condition and to store the application triggering condition and the execution information of the new application in an application information database, when the intersections do not exist or the conflict resolution policy has been defined, an explicit conflict processing unit to select an application to be executed from among the explicit conflict set according to the application triggering condition and the conflict resolution policy of each application which are stored in the application information database, and an implicit conflict processing unit to determine whether to execute or cancel an API in the implicit conflict set according to a conflict resolution policy when the API is called.