The invention, which belongs to the technical field of security stealing prevention equipment, provides an intelligent phone anti-theft device comprising a plastic shell, a buckle, a display device, a keyboard, a main circuit board, a USB charging interface, and a switch button. The intelligent phone anti-theft device is characterized in that the plastic shell has a circular shape; the USB charging interface and the switch button are arranged at the side of the device; and the keyboard and the display device are arranged at the upper surface of the device. The main circuit board arranged inside the plastic shell is composed of a rechargeable battery, a processor, a bluetooth communication circuit, a buzzer, and a vibrator; the switch, the display device, the keyboard, the USB charging interface and the button are electrically connected to the main circuit board. The device connected with a mobile phone wirelessly by means of Bluetooth. When the mobile phone is taken away beyond a security distance or connection with the mobile phone is cut off, the device and the mobile phone generate vibration instantly and simultaneously and send out alarming sounds, so that the user can discover the stealing of the mobile phone timely and thus find out a thief easily.