An imaging system includes an imaging device connected to a first communication network, and a first server device connected to the first communication network, and each of the imaging device and the first server device includes a first logical port that is used to transfer video data, a second logical port that is used to transfer data other than the video data, a measuring unit that measures a data transfer amount of the second logical port, and a band control unit that controls transfer bands of the first logical port and the second logical port according to the data transfer amount measured by the measuring unit.