A variable valve actuation apparatus includes a lock pin slidably disposed in a slide bore formed in a rotor of a vane rotor, a retaining hole formed in an inner face of a sprocket, and a lock-hole structural member fixed and press-fitted into the retaining hole and configured to form the lock hole. The retaining hole is formed at the innermost peripheral side of the sprocket so as to face a central support bore of the sprocket. The inner end face of a large-diameter bore of the retaining hole is formed as a flat surface, whereas the outer end face of a lock-hole structural section of the lock-hole structural member is formed as a planar section. The lock-hole structural member is precisely positioned in its rotation direction by abutment between the flat inner end face and the planar outer end face.