The invention discloses a dictograph discovering, locating and alarming system and method. The system comprises a frequency spectrum monitoring device, a video monitoring device, a data processing center, a video processing center, a service center and a mobile terminal, wherein the frequency spectrum monitoring device acquires a signal value of current environment and uploads the signal value to the data processing center; the video monitoring device acquires video content of the current environment and uploads the video content to the video processing center; the data processing center analyzes and processes the acquired signal value, identifies whether a GSM signal exists in the current environment, locates a signal source and uploads the location result to the service center; the video processing center is used for identifying whether activity of a person exists in the current environment and uploading a video content and judgment result to the service center; in the current environment, the service center comprehensively judges whether a dictograph exists and data is published; the mobile terminal implements remote access of the service center by a user in an APP form. According to the dictograph discovering, locating and alarming system and method, the accuracy of discovery and identification of the dictograph is improved, and the guarantee of environment information security is implemented.