A new type of photonic crystal fiber with elliptical air holes in the center is designed, and we study the properties including electric field distribution, birefringence, dispersion, nonlinearity, and confinement loss of fundamental mode of this fiber by using full vector finite element method. The results show that the electric field energy is bound in the fiber core. The birefringence can be reached 5.958×10-2, which reaches the magnitude of 10-2 at a wavelength of 1.55 μm. In the wavelength range from 1.50 μm to 1.60 μm, the dispersion is (-549.2±5) ps/(nm·km), which is a highly flattened negative dispersion. The nonlinear coefficient in x-polarization of this fiber is 46.82 W-1·km-1, and the low confinement loss is 5.413×10-4 dB/km at 1.55 μm, and the confinement losses of the polarization states in the y direction are 6423 times than those in the x direction. The proposed photonic crystal fiber has the characteristic of high birefringence, high nonlinearity, highly flattened negative dispersion, and low confinement loss, which could be widely used in the field of optical fiber sensing, polarization control, dispersion compensation, nonlinear optics and so on.