1. A process control system comprising: a client computer which prepares a correlation between a reference monitored value of apparatus information indicating a processing state of a manufacturing apparatus in a reference manufacturing process with respect to a reference wafer, and a feature quantity obtained from a control parameter for controlling the manufacturing apparatus and a finished form in the reference manufacturing process; a manufacturing execution system which prepares a processing recipe describing, as a first setting value of a first step in an actual manufacturing process with respect to an objective wafer, a value of the control parameter calculated on the basis of a dimension of a processing objective structure in the actual manufacturing process; an apparatus information collection section which collects an objective monitored value of the apparatus information from the manufacturing apparatus in operation of the actual manufacturing process with the first setting value; a feature quantity calculation section which calculates a value of a feature quantity corresponding to the objective monitored value on the basis of the correlation; a parameter calculation section which calculates a second setting value of a second step in the actual manufacturing process following the first step of the actual manufacturing process on the basis of the value of the feature quantity corresponding to the objective monitored value; and an apparatus control unit which changes the processing recipe with the second setting value being as a setting value of the second step.