A synthetic danger predicting and disaster preventing monitor system, comprising synthetic sensors attached to both end portions of piping positioned across each of a plurality of specific intervals at required portions of a network of water distributing pipelines to detect signals of abnormality in connection with at least sound, radiation, heat, mechanical strain, potential difference between the piping and a contact portion of each synthetic sensor with the underground earth, electricity, magnetism and vibration, a wireless transmitting means for emitting radio waves to a communications satellite from a wireless data transmitter means through a parabolic antenna fitted to the outer circumferential portion of a manhole cover after the data signals are subjected to A-D conversion, a receiving means for data signals transmitted in the form of radio waves by the communications satellite, a data processing means in which the received data signals are inputted and are analyzed for each specific interval in the pipeline to check for abnormality, and if the data signals are judged to be those of abnormality information, any specific interval producing the signals of abnormality information, a display unit for information of abnormality in which upon receipt of signals from the data processing means, at least the specific interval producing the signals of abnormality information is indicated on a displaying screen of the pipelines including specific intervals located and revealed from a network of water distributing pipelines on a map, a monitoring screen to indicate the position of trouble occurrence, a monitoring screen for indicating particulars of trouble in each pipeline, and a printer means whereby a place and particulars of trouble are located or presumed before disaster results so that a danger can be predicted.