A plant operating condition setting support system for supporting the setting of a plant operating condition includes: a learning device that learns a regression model for calculating, from values of a plurality of state parameters indicating an operating condition of a plant and values of a plurality of manipulation parameters set to control an operation of the plant, a predicted value of an output indicating a result of operating the plant when the values of the plurality of manipulation parameters are set in the operating condition indicated by the values of the plurality of state parameters; and an operating condition setting support device that calculates the values of the plurality of manipulation parameters that should be set to control the operation of the plant, by using the regression model learned by the learning device.