The dispersion characteristics of photonic crystal fibers are calculated by multipole method.Single mode fibers with three zero-dispersion wavelengths are obtained by the accuracy design of the fiber structure parameters.Closing to zero and flattened dispersion can be obtained in the fibers with three zero-dispersion wavelengths.The special phase-matching characteristics of the fibers with three zero-dispersion wavelengths are analyzed.The variation of phase-matching wavelength with the pump wavelength and the pump power is obtained for the different fiber structure parameters.The characteristics of phase-matching wavelength for different dispersion curves are analyzed.The presence of three zero-dispersion wavelengths can realize the high efficiency wavelength conversion of optical soliton between two anomalous dispersion regions,get six new four- wave mixing phase- matching wavelengths and produce more photon pairs.These provide a new physical condition for efficient multiple wavelength four-wave mixing and supercontinuum spectrum research.