A 2×2 thermo-optic digital optical switch with one electrode is designed and fabricated using polymers; BCB for core layer and UV-15 for cladding layer. The polymer waveguide is fabricated by the reactive ion etching method. The fabricated device has the wavelength-independent and polarization-independent properties. The measured crosstalk for each path is less than -15 dB. The average power consumption is about 64 mW.