An air-fuel ratio control device of an internal combustion engine, the engine including a variable valve lift mechanism, which changes the lift amount of an intake valve, and a sensor that outputs a signal corresponding to the oxygen concentration in exhaust gas, wherein, when an execution condition of feedback control is not met after operation of the engine has been started, the control device sets a fuel injection amount command value through prediction control based on the operating condition of the engine, and when the execution condition is met, the control device sets the fuel injection amount command value through the feedback control using a correction amount for correcting fuel injection amount, the correction amount being computed based on the output value of the sensor, wherein a region of the lift amount includes a first lift amount region used when the execution condition is met and not met, wherein the first lift amount region is a region including an upper limit lift amount, and the execution condition is met when a coolant temperature of an engine coolant of the internal combustion engine, the coolant temperature being determined by a temperature sensor comprised by the control device, is higher than or equal to a predetermined temperature and the sensor is activated, and a second lift amount region used only when the execution condition is met, the control device comprising: a learning section, wherein, when the execution condition is met and a learning condition is met, the learning section learns, as a deviation amount learned value, a deviation amount between the correction amount and a reference value of the correction amount in each of a case in which the lift amount is in the first lift amount region and a case in which the lift amount is in the second lift amount region, the learning section computes and stores the relationship between the deviation amount and the lift amount based on the deviation amount learned value; and a correction section that computes a deviation amount correction value from the stored relationship and based on the lift amount, and corrects the fuel injection amount command value using the deviation amount correction value, the control device being characterized by an inhibiting section, wherein, when there is no record of completing learning of the deviation amount for the first lift amount region, the inhibiting section inhibits the lift amount from being shifted from the first lift amount region to other lift amount region regardless of whether the learning condition is met. a learning section, wherein, when the execution condition is met and a learning condition is met, the learning section learns, as a deviation amount learned value, a deviation amount between the correction amount and a reference value of the correction amount in each of a case in which the lift amount is in the first lift amount region and a case in which the lift amount is in the second lift amount region, the learning section computes and stores the relationship between the deviation amount and the lift amount based on the deviation amount learned value; and a correction section that computes a deviation amount correction value from the stored relationship and based on the lift amount, and corrects the fuel injection amount command value using the deviation amount correction value, the control device being characterized by an inhibiting section, wherein, when there is no record of completing learning of the deviation amount for the first lift amount region, the inhibiting section inhibits the lift amount from being shifted from the first lift amount region to other lift amount region regardless of whether the learning condition is met.