In a polarization-independent light control element operable at low voltage, optical waveguides are provided in an X-cut first substrate and control electrodes are disposed thereabove. Optical waveguides are provided in a Z-cut second substrate and control electrodes are disposed thereabove. The control electrodes of the first and second substrates are connected in series to each other in the propagation direction of light. This allows a transverse electric component and a transverse magnetic component to be efficiently controlled because of the incorporation of high electro-optical effects of the optical waveguides of the first substrate on the transverse electric component and high electro-optical effects of the optical waveguides of the second substrate on the transverse magnetic component.