In order to improve the birefringence and sensing sensitivity of optical fiber, a photonic crystal fiber based on elliptical hole array is proposed. The refractive index distribution of optical fiber is modulated by air holes, which effectively improves the birefringence of optical fiber. Based on the full vector finite element analysis method, the dispersion, limiting loss and temperature sensing characteristics of optical fiber are studied. The simulation results show that the birefringence of the fiber is as high as 1. 92X10-2 when the ellipticity of hole array is 2. The limiting loss is as low as 10-10 dB/km, and the dispersion is about -15. 54ps . km-1 . nm-1. The thermos-optic coefficient of the fundamental mode of the optical fiber is effectively improved by filling liquid for sensitization, and the thermos-optic coefficient is up to 9.5×10-5/C, which can be used for optical fiber high sensitivity temperature sensing.