A kind of electric knife-pen includes a circuit board, complex operation key, a switch controller and an outer housing. Circuit board is suitable to be fixed and be electrically connected with a metal electrode, complex operation key system device what circuit board, and between switch controller system sandwiched what circuit board and complex operation key, and outer housing is suitable can accommodate circuit board, complex operation key and switch controller. Wherein, switch controller has a polygonized structure, and when switch controller is by auxiliary plate device what circuit board Hou, accessory plate will separate switch controller.一種電刀筆，包含一電路板、複數操作按鍵、一開關控制器及一外殼體。電路板適可與一金屬電極固定並電性連接，複數操作按鍵係裝置於電路板，開關控制器係夾設於電路板與複數操作按鍵間，且外殼體適可容置電路板、複數操作按鍵及開關控制器。其中，開關控制器具有一多邊形結構，當開關控制器藉由一輔助板裝置於電路板後，輔助板將拆離開關控制器。
