The invention relates to an intelligent doorbell, consisting of a mobile phone mainboard, a plastic shell, a guest coming prompt circuit, a trigger circuit, a startup circuit, a control circuit, a dialing circuit, a detection circuit, a first time delay circuit, a second time delay circuit, a password mechanism, a recharge socket and a prompt circuit, wherein the mobile phone mainboard, the guest coming prompt circuit, the trigger circuit, the startup circuit, the control circuit, the dialing circuit, the detection circuit, the first time delay circuit, the second time delay circuit, the password mechanism, the recharge socket and the prompt circuit are connected with one another by leads and are installed in the plastic shell; the plastic shell is installed in a groove at the left end of the side, positioned in the home, of a security door. The intelligent doorbell has a function of guest coming prompt, can automatically have a remote communication with an owner by means of the mobile phone mainboard under the action of the related circuits when no one is at home, and also has the functions of preventing burglary and monitoring the safety of elderly people living alone at home for 24h; a battery in the mobile phone mainboard only needs to be charged for once very half a year under the normal service condition, so that the inconvenience, caused by frequently charging, to a user can be prevented.