An alert generating method for a radio paging receiver that performs the steps of generating a continuous alert signal having a predetermined alert frequency using a timer circuit disposed in a microcontroller of a radio paging receiver when self information of the radio paging receiver is detected from a received radio paging signal and generating an alert in response to the continuous alert signal. The step of generating a continuous alert signal further performs the steps of scaling a frequency of an input signal to a second predetermined frequency, setting the predetermined alert frequency, comparing the second predetermined frequency to the predetermined alert frequency and generating the continuous alert signal having the predetermined alert frequency, when the second predetermined frequency matches the predetermined alert frequency. The alert generating device for use in a radio paging receiver comprises an antenna, a radio circuit for frequency-converting, demodulating, and waveform-shaping the received radio paging signal to generate digital data, a decoder for decoding the digital data, and a microcontroller having a timer circuit, the microcontroller analyzing the decoded data to determine if the decoded data includes self information of the radio paging receiver, and generating a continuous alert signal having a predetermined alert frequency using the timer circuit, when the decoded data includes the self information.