Vortex generators for wind turbine rotor blades having noise-reducing features are mounted within a laminar flow region on either the pressure side or the suction side of the rotor blade and have a base portion with at least one airflow modifying element extending therefrom. The base portion has a leading edge and a trailing edge extending in a first direction. Further, the base portion includes one or more edge features formed within either or both of the leading or trailing edges. Moreover, the edge features are non-parallel with respect to the first direction so as to reduce laminar boundary layer instability noise.