a combination housing of a notebook computer having a display housing and a main frame housing . the main frame housing including a top metal cover , a first middle plastic frame , and a bottom metal cover three of which are combined to form a sandwich structure . meanwhile , the main frame housing including a front metal cover , a second middle plastic frame , and a rear metal cover three of which are combined to form a sandwich structure . besides , an engagement of engaging parts of the metal covers in corresponding arched cavities of the middle plastic frames is utilized to permit a rapid fastening . in this way , the main housing portion of the notebook computer can be made of aluminum ally or aluminum magnesium alloy .