A control apparatus for an internal combustion engine, comprising: a variable operating angle mechanism which makes an operating angle of an intake valve variable; operating angle control means which controls the variable operating angle mechanism based on an operating angle command value relating to the operating angle of the intake valve; air amount acquisition means which acquires an intake air amount of the internal combustion engine; estimation means which estimates a maximum operating angle command value at which the intake air amount indicates a maximum value in association with a change of the operating angle command value, based on a value of the intake air amount acquired during a control of the operating angle of the intake valve based on each of the operating angle command values of at least two points; and correction means which corrects a deviation of a valve timing of the intake valve by comparing the maximum operating angle command value estimated by the estimation means with a reference value, wherein the internal combustion engine further comprises: a variable phase mechanism which makes a rotational phase of an intake cam that drives the intake valve variable with respect to a rotational phase of a crankshaft; and phase control means which controls the variable phase mechanism based on a phase command value relating to the rotational phase of the intake cam, and wherein the phase control means includes phase locking control means for controlling the variable phase mechanism such that the rotational phase of the intake cam coincides with a fixed value at a start of estimation of the maximum operating angle command value by the estimation means. a variable operating angle mechanism which makes an operating angle of an intake valve variable; operating angle control means which controls the variable operating angle mechanism based on an operating angle command value relating to the operating angle of the intake valve; air amount acquisition means which acquires an intake air amount of the internal combustion engine; estimation means which estimates a maximum operating angle command value at which the intake air amount indicates a maximum value in association with a change of the operating angle command value, based on a value of the intake air amount acquired during a control of the operating angle of the intake valve based on each of the operating angle command values of at least two points; and correction means which corrects a deviation of a valve timing of the intake valve by comparing the maximum operating angle command value estimated by the estimation means with a reference value, wherein the internal combustion engine further comprises: a variable phase mechanism which makes a rotational phase of an intake cam that drives the intake valve variable with respect to a rotational phase of a crankshaft; and phase control means which controls the variable phase mechanism based on a phase command value relating to the rotational phase of the intake cam, and a variable phase mechanism which makes a rotational phase of an intake cam that drives the intake valve variable with respect to a rotational phase of a crankshaft; and phase control means which controls the variable phase mechanism based on a phase command value relating to the rotational phase of the intake cam, and wherein the phase control means includes phase locking control means for controlling the variable phase mechanism such that the rotational phase of the intake cam coincides with a fixed value at a start of estimation of the maximum operating angle command value by the estimation means.