The invention relates to an air-fuel ratio control device of an internal combustion engine, comprising a plurality of means for independently introducing into each combustion chamber an exhaust gas discharged from combustion chambers to an exhaust passage. When at least one exhaust gas introduction means is under an exhaust gas introduction shortage state, a target value of an air-fuel ratio of a mixture gas is changed depending on whether an exhaust gas introduction control for introducing the exhaust gas into the combustion chamber by the exhaust gas introduction means is performed.