A production facility monitoring system comprising: a feature amount acquisition unit configured to acquire values of plural types of feature amounts that are calculated from operating state data indicating an operating state of a production facility that produces a product, for both a normal time at which the production facility produces the product normally and a defective time at which a defect occurs in the product that is produced, the feature amount showing a feature of the production facility; characterized in that a prediction model creation apparatus further comprises: a feature amount selection unit configured to select a feature amount effective in predicting the defect that occurs in the product that is produced from among the acquired plural types of feature amounts, based on a predetermined algorithm that specifies a degree of association between the defect and the types of feature amounts, from the values of the types of feature amounts acquired at the normal time and the defective time, wherein the feature amount selection unit is configured to select that feature amount having the highest degree of association between the defect and the selected feature amount out of the acquired plural types of feature amounts or that feature amount being designated by a user; a prediction model construction unit configured to construct a prediction model for predicting occurrence of the defect, using the selected feature amount; and a monitoring apparatus configured to acquire operating state data from the production facility during operation, calculate a value of the feature amount used in the prediction model from the acquired operating state data, and determine whether there is an indication of defect occurrence in a product that the production facility produces, by applying the calculated value of the feature amount to the prediction model. a feature amount acquisition unit configured to acquire values of plural types of feature amounts that are calculated from operating state data indicating an operating state of a production facility that produces a product, for both a normal time at which the production facility produces the product normally and a defective time at which a defect occurs in the product that is produced, the feature amount showing a feature of the production facility; characterized in that a prediction model creation apparatus further comprises: a feature amount selection unit configured to select a feature amount effective in predicting the defect that occurs in the product that is produced from among the acquired plural types of feature amounts, based on a predetermined algorithm that specifies a degree of association between the defect and the types of feature amounts, from the values of the types of feature amounts acquired at the normal time and the defective time, wherein the feature amount selection unit is configured to select that feature amount having the highest degree of association between the defect and the selected feature amount out of the acquired plural types of feature amounts or that feature amount being designated by a user; a prediction model construction unit configured to construct a prediction model for predicting occurrence of the defect, using the selected feature amount; and a monitoring apparatus configured to acquire operating state data from the production facility during operation, calculate a value of the feature amount used in the prediction model from the acquired operating state data, and determine whether there is an indication of defect occurrence in a product that the production facility produces, by applying the calculated value of the feature amount to the prediction model.