This application provides an alarming method and device, and relates to the field of communications. The method includes: obtaining a power of an audio signal; determining a transmit power value at least according to the power of the audio signal; broadcasting detection information according to the transmit power value, the detection information including the transmit power value; and alarming, in response to receiving alarming information fed back by another device according to the detection information, a user according to the alarming information. According to the method and device, a user is alarmed in time in a situation in which a risk may occur, and meanwhile an undesired effect of an environmental noise on the user listening to the audio signal in a safe situation is also avoided, thereby improving user experience.