Control device and method for internal combustion engine

A control device for an internal combustion engine comprising an EGR passage (22) for communicating an intake passage (17) and an exhaust passage (18) with each other, an EGR valve (24) provided in the EGR passage (22), and an intake throttle valve (19) provided in the intake passage (17) at an upstream side of the connection part with the EGR passage (22). The control device comprises operational state detection means for detecting an operational state of the internal combustion engine, first control means for controlling opening and closing of the intake throttle valve (19) and the EGR valve (24) to adjust intake air volume if the operational state detection means detects a normal operational state, and second control means for controlling the intake throttle valve (19) at a predetermined constant opening degree and for controlling opening and closing of the EGR valve (24) to adjust an intake air volume if the operational state detection means detects a predetermined operational state.