The present invention can operate a CRT operation of a plant device not only from a limited place such as a central handling room but also from a job site in a CRT operation system. In this CRT operation system for operating and monitoring the plant device 31 from the central handling room through a network 35, a personal computer 30 for operating and monitoring the plant device at the job site is installed, a radio LAN transmitter-receiver 36 for performing transmission and reception to/from the personal computer by radio is installed at an important point that is subjected to rounds of inspection of the job site, the personal computer for operation transmits an operation request through the radio LAN transmitter-receiver and the network to operate the plant device, the operating state of a job site is transmitted to the central handling room, and the operating state is displayed and reported on/from a display device 33 and a sound output device 34 of the handling room, respectively. |