The invention yet notify the danger signal, if the emergency to ensure that provided with the Bluetooth wireless communication is to install the speaker device capable of, and a timer device and a USB chip for self-defense whistle, Normally, listening to music, the time identified, the program and the file sharing function and an object of the present invention is to provide a multifunction self-protection to whistle. Housing The present invention made of any of materials of plastic or metal for this purpose; It is formed in the housing and tone generation section for generating a tone through the air and vibration; It is installed on one side of the housing, the radio communication with the smart device and the Bluetooth system, and speaker unit for outputting sound; Installed on the upper surface of the housing, indicating the time digitally using a liquid crystal display is the timer unit; USB memory unit which is installed on the other side of the housing, so that they can share a program file; And it comprises the hook portion coupled to the housing, so that the user can place on the neck. Therefore multi-functional self-defense whistle according to the present invention, if the emergency to ensure that includes installing a speaker device capable of Bluetooth wireless communication in the self-defense whistle, and with a timer device and a USB chip has yet notify the danger signals, usually, the music listening and time identifying there is an advantage capable of providing a program and file sharing.