Provided are a camera, a system for remote viewing and talking, and its application. The camera includes a camera shielding case, a holder, and a cloud deck shielding case, the holder is a hollow structure, and a cavity of the camera shielding case is communicated with a cavity of the cloud deck shielding case through the holder with the hollow structure; a lens, a camera mainboard, an optical fiber transceiver, and a first filter are arranged in the camera shielding case; the camera shielding case is further provided with a power line hole and an optical fiber interface; the optical fiber transceiver is connected with the optical fiber interface through an optical fiber; output ends of the first filter are connected with the camera mainboard and the optical fiber transceiver respectively to supply power to the camera mainboard and the optical fiber transceiver.