The dispersion characteristics of photonic crystal fibers (PCF) are simulated numerically by the multipole method.It is proved to be accurate contract with the experiment data.We have studied the effect of the structural parameters on dispersion properties such as hole diameter,pitch and the number of the hole rings.It shows that the zero-dispersion wavelength can be shifted by changing the pitch or hole diameter.When Nr is small,the dispersion properties of the photonic crystal fibers have large differentiation;but when Nr is larger the dispersion properties will no longer change.The calculation and the analysis provides a certain theoretical base with the design of photonic crystal fibers with desirable dispersion.