The invention relates to an assembling method and system for an application program. The assembling method and system are used for assembling an installation package which can be installed on the application program of user equipment. The system comprises a user interface module selection unit used for selecting a user interface module matched with the screen of the user equipment according to the screen information of the user equipment, and an installation package assembling unit used for assembling the corresponding user interface module chosen by the user interface module selection unit and an operation logic module to form the installation package of the application program, wherein the operation logic module is not related to the screen of the user equipment.