The present invention provides a traffic flow and vehicle safety and position detection system, which includes a vehicle detection host within a vehicle, a remote server system and a mobile telephone number. When being used to monitor traffic flow, GPRS (General Packet Radio Service) is used to link up the vehicle detection host with the remote server system and transmit traveling vehicle information to a remote server, wherein the information is stored. When being used to prevent vehicle theft, a vehicle owner is able to phone the remote server system via the mobile telephone number, thereby enabling the remote server system to detect location of the vehicle detection host. Hence, the mobile telephone number enables the vehicle owner to have control over the status of his vehicle at all times.