A method and apparatus is provided for providing a mobile advertising service in a mobile advertising system, and for sharing a preference to deliver a personalized advertisement requested by a particular group member to other users. In a method for providing a mobile advertising service by a server of a mobile advertising system, a group creation request message including a user list and a group user preference is received from an advertising engine, a group is created according to the user list and the group user preference in the group creation request message, a response message to the group creation request message is sent to the advertising engine, an advertisement request message is received from one of advertising engines included in the user list, an advertisement appropriate for the group user preference is selected, and the selected advertisement is delivered to at least one advertising engine included in the user list. The at least one advertising engine is included in the same group.