A novel en-/de-coder scheme based on super-structure optical fiber gratings is proposed for optical code division multiple access(OCDMA)system.It can realize code in wavelength domain and avoid the shortcoming of the loss generated by conventional multiple fiber gratings in series.And the en-/de-coder scheme can easily adjust the center wavelength by changing strain or temperature.It is very small and very tunable.These features lead to commercialization.The en-/de-coder scheme based on super-structure optical fiber gratings with 0.8 nm interval is researched.It is shown that changing address is achieved by center wavelength drift of super-structure optical fiber gratings by changing the temperature.