A control apparatus that can partially identify model parameters is provided. The apparatus for controlling an object that is modeled using at least one first model parameter and at least one second model parameter comprises a partial model parameter identifier for recursively identifying the second model parameter based on an output from the object and an input into the object, and a controller for using the first model parameter that is pre-identified and the second model parameter identified by the partial model parameter identifier to determine an input into the controller so that the output from the object converges to a desired value. Since all model parameters are not required to be recursively identified, the time for causing the model parameters to converge to optimal values can be shortened. The computational complexity for the identifier can be reduced.