Abstract: This invention relates to a functional module structural improvement for expanded and enhanced SIM card comprising of an user identification module and a SIM card; the user identification module is formed by thin film circuit board, the surface is installed with electrical connection points and a control chip, the control chip is built in with: operational interface and functional selection items, application information of the original line number, and more than one sets of new number information, operational interfaces, functional selection items, application information; it can provide the user with more diversified and total functional interface application as well as multi-number selection and usage switching, the convenience and effectiveness of usage can thus be greatly enhanced.