To provide a small-sized alarm generator capable of easily sensing the whereabout of variables of each person by effectively using the radio signal of a portable telephone or the like.

This alarm generator has a receiving means for receiving a radio signal and a voice generating means for amplifying the signal received by the receiving means to emit a prescribed voice which are provided in a thin plate-like case, and is constituted so as to generate a prescribed alarm from the voice generating means when a prescribed radio signal from a telephone is received by the receiving means. The case is formed in a substantially flexible sheet form, and the carry-on article is a portable variable article such as key, purse or the like.