In this paper, a 2×2 total internal reflection optical switch is designed and successfully fabricated by employing the thermo optic effect of polymeric materials. The extinction ratios of the non block 2×2 optical switch are larger than 27 dB at both the crossing and reflecting states. The driving power at the totally reflecting states is about 132 mW with a driving voltage of about 3 V and a related electric current of 44 mA. This driving voltage can be decreased to 50～60 mW by adopting electroplating. The insertion loss is also measured.