Transmission property of a FCC structure three-dimensional photonic crystal was studied by transfer matrix method. The transmission properties of the photonic crystal with a point-defect,a line-defect and a plane-defect respectively were mainly analyzed. The defect model will appear when a defect exists in the photonic crystal. The correlation between the defect property and its permittivity ε,radius γ,location was obtained. These conclusions are beneficial to designing optical communication devices such as photonic crystal WDM filters and photonic crystal waveguide.