A control apparatus for an internal combustion engine comprising: an internal combustion engine including at least one recirculating gas generating cylinder (#1, #4) capable of recirculating a part of its exhaust gas to an intake system and at least one recirculating gas nongenerating cylinder (#2, #3) that does not recirculate its exhaust gas to the intake system; an exhaust gas recirculating path having one end connected to an exhaust path through which exhaust gas only from the recirculating gas generating cylinder (#1, #4) flows and having the other end connected to the intake system; an exhaust catalyst for purifying exhaust gas provided on an exhaust path through which exhaust gas from the recirculating gas generating cylinder (#1, #4) and the recirculating gas nongenerating cylinder (#2, #3) flows; a recirculating catalyst provided on the exhaust gas recirculating path for purifying exhaust gas that recirculates to the intake system; fuel cut means that executes fuel cut for temporarily stopping fuel injection of the internal combustion engine; and rich control means that performs rich control for controlling an air-fuel ratio of the internal combustion engine to be temporarily richer than a theoretical air-fuel ratio when the fuel injection is restarted after return from the fuel cut, wherein the rich control means includes air-fuel ratio control means that controls an air-fuel ratio in the recirculating gas generating cylinder (#1, #4) to be richer than an air-fuel ratio in the recirculating gas nongenerating cylinder (#2, #3) when the rich control and an exhaust gas recirculation by the exhaust gas recirculating path are simultaneously performed. an internal combustion engine including at least one recirculating gas generating cylinder (#1, #4) capable of recirculating a part of its exhaust gas to an intake system and at least one recirculating gas nongenerating cylinder (#2, #3) that does not recirculate its exhaust gas to the intake system; an exhaust gas recirculating path having one end connected to an exhaust path through which exhaust gas only from the recirculating gas generating cylinder (#1, #4) flows and having the other end connected to the intake system; an exhaust catalyst for purifying exhaust gas provided on an exhaust path through which exhaust gas from the recirculating gas generating cylinder (#1, #4) and the recirculating gas nongenerating cylinder (#2, #3) flows; a recirculating catalyst provided on the exhaust gas recirculating path for purifying exhaust gas that recirculates to the intake system; fuel cut means that executes fuel cut for temporarily stopping fuel injection of the internal combustion engine; and rich control means that performs rich control for controlling an air-fuel ratio of the internal combustion engine to be temporarily richer than a theoretical air-fuel ratio when the fuel injection is restarted after return from the fuel cut, wherein the rich control means includes air-fuel ratio control means that controls an air-fuel ratio in the recirculating gas generating cylinder (#1, #4) to be richer than an air-fuel ratio in the recirculating gas nongenerating cylinder (#2, #3) when the rich control and an exhaust gas recirculation by the exhaust gas recirculating path are simultaneously performed.