To provide a plant operation support system, appropriately transmitting a preannouncement display for future operation schedules to an individual worker in a plant according to the work skill level of the worker concerned, eliminating inappropriate operation of the plant due to an operation mistake resulting from habituation in operations, and easily and rapidly identifying the cause thereof, in the event of any abnormal situation for operating state of the plant.

This system comprises a plant control device for controlling all operation processes of the plant, and a plant monitoring device connected to the plant control device through a network to monitor operating states of facilities or equipment of the plant. When a worker confirms each operation procedure based on the operation processes of the plant, the work skill level of each worker working in the plant is confirmed based on ID information of the worker concerned, and an operation procedure preannouncement based on this work skill level is displayed on a display device of the plant control device or the plant monitoring device.