PURPOSE: To considerably improve the cost of fuel by switching a control method corresponding to the early and exact judgement of timing and more extending a lockup area when a controlled system is defined as a lockup clutch concerning the controller for the controlled system, which is non-linear or deformed at abnormal time, to change a system for each part of a control, area.

CONSTITUTION: This device is provided with a state estimating means c1 for estimating the state of the system by identifying the system while applying a control output, system output and state amount, system holding means d1 for holding the system provided by the system identification executed in the past, comparing means e1 for comparing the system provided by the system identification newly executed this time with the system provided by the system identification executed in the past, and control switching means f1 for switching the control method when the difference of two systems is judged by the system comparison.