A photonic crystal fiber (PCF) with octagonal microstructure is designed in this paper, and the characteristics of the fundamental mode of the fiber, such as dispersion, nonlinear coefficient and confinement lose, are studied based on the finite element method. The results show that, by properly adjusting the structural parameters of the fiber, there is a zero dispersion point at a wavelength of1.55 μm, and at this wavelength, it has highly nonlinear coefficient of 94.97 W^-1?km^-1 and low confinement lose of 3.065 × 10^-6 dB/km. This design provides theoretical guidance for obtaining zero dispersion, highly nonlinearity and low confinement lose at a wavelength of 1.55 μm, and has potential applications in dispersion control, nonlinear optics, and other fields.