An intersectional optical switch structure with an intersecting angle of 6° was fabricated on an organometallic vapor-phase epitaxy (OMVPE) grown GaInAs/InP multiple quantum-well (MQW) layered wafer. Switching operation using field-induced refractive index variation was successfully demonstrated at the reverse bias voltage of 8 V for the 1.6 μm wavelength region. Based on this switching, the field-induced refractive index variation in the QW was estimated as around 1%.