An Internet-of-Things (IoT) system for public transportation service and a method of operating the same are disclosed. The IoT system includes on-vehicle devices, a management server, a plurality of bus stop access points (APs), and a wired/wireless bus stop access point (AP) communication network. The on-vehicle devices are mounted within a bus, i.e., a public transportation means. The management server is connected to the bus over an Internet, i.e., a wireless communication means. The plurality of bus stop APs are short distance communication APs, and are each provided in each bus stop at which the bus stops and configured to enable information to be exchanged between the bus stop and the bus. The wired/wireless bus stop AP communication network connects the plurality of bus stop APs. The management server performs Internet access processing to connect the bus stop AP communication network and an external terminal.