A variable valve timing control device includes a housing member, a rotor member assembled to the housing member so as to be rotatable relative thereto and including vane portions each forming an advanced angle chamber and a retarded angle chamber within the housing member, a stopper formed on the convex portion for restricting a relative rotation between the housing member and the rotor member, a lock mechanism for restricting the relative rotation by a lock member, and a fluid pressure circuit for controlling an operation oil to be supplied to or discharged from the advanced angle chamber, the retarded angle chamber, and the lock mechanism. When the relative rotation is restricted, the lock member is in contact with an inner peripheral face of the receiving hole on the advanced angle side and the retarded angle side between an opening portion and a bottom portion of the receiving hole.