By employing the liquid crystal refractive index changes induced by an applied electric field, a polarization rotator was proposed based on liquid crystal infiltrated tellurite photonic crystal fiber. The mode field distribution of the fiber fundamental mode and the influence on polarization rotation of some parameters were simulated by using full vector finite element method. The results show that, this polarization rotator has a high work efficiency, low crosstalk and short conversion length. With the wavelength of 1.55 μm and the polarization angle of 45°, the values are 99.95%, －32.84 dB and 197 μm, respectively. The conversion length of the fiber becomes longer, when the thin wall thickness of grapefruit photonic crystal fiber is increasing or the temperature is decreasing. While the working wavelength is increasing, the conversion length of the fiber becomes shorter. The liquid crystal infiltrated tellurite photonic crystal fiber has a good polarization rotation performance, offering a reference for the design of polarization rotator, which is useful for making compact and diverse polarization rotation devices.