A kind of thermo-optic polymer micro-ring resonator filter is designed and fabricated.A racetrack is used in the micro-ring resonator.By using beam propagation method(BPM),the bending radius is designed and optimized.The micro-ring resonator is fabricated by using the traditional contact lithography technology.Experiment results show that around the wavelength of 1 550 nm,the micro-ring resonator′s free spectral range,extinction ratio,3 dB bandwidth,Q factor and modulation efficiency are about 112 pm,12.8 dB,0.026 nm,5.96×104 and 6.13 pm/mW,respectively.The response time of the filter is about 1.5 ms.