Based on phase Shifted Superstructure Fiber Bragg Grating(SSFBG),the structure and bipolar encoding/decoding principles of an Optical Code Division Multiple Access(OCDMA) system were researched and its correlation property was simulated by transmission matrix method.The effect of Bragg wavelength deviation due to the mismatch of the grating period between encoder and decoder on correlation property was analyzed theoretically.The results indicate that the correlation property is improved with the increasing of code length,but it is more sensitive to the deviation of Bragg wavelength between encoder and decoder when the code length is increased and the chip pulse width is fixed.To obtain desired correlation property,the deviation of Bragg wavelength between encoder and decoder must be less than 0.02 nm for the Gold sequences with length of 31 and chip duration of 6 ps at 1.555 μm.It is conclusion that a code can be used in different Bragg wavelengths to implement hybrid Wavelength Division Multiple(WDM) OCDMA system.