The invention discloses an acetylaminobenzo[d]azepinquinazoline compound as well as preparation and application thereof. The invention provides a novel quinazoline compound with very good anticancer (particularly human breast cancer) activity, which is expected to be applied to preparation of medicines for preventing or treating the human breast cancer. A preparation method of the acetylaminobenzo[d]azepinquinazoline compound, provided by the invention, is simple and easy to operate; raw materials are easy to obtain; the production cost is relatively low; the preparation method is suitable forpractical use.