The Content of this article is about a design scheme of a 110 reporting- to- police system based on city telephone subscriber Line. By using the service work that the telecommunication bureau provides caller information to subscriber ( inserts caller number and other relevant information between the first and the second ringing of the subscriber terminal) , this scheme sets up a platform using binary frequency shift keying ( FSK) decode technique on the subscriber side, receives the caller ( reporting side) telephone number, then through the data base in the service equipment, finds the caller ( reporting side) material and information, and chooses the corresponding police action plan.