The rapid expansion of multimedia services could lead to improve network accessibility with multiple users simultaneously. The technological development in asynchronous communication considered system performance as one of the major issues. Simultaneous accessing of the channel from the multiple stations is one of the techniques. Traditionally multiple access for the channel is playing an important role in multiple asynchronies communication. Optical Code Division Multiple Access (OCDMA) is one of the advanced techniques used in accessing the asynchronous network due to its inherent capability. OCDMA provides dynamic bandwidth support for multimedia services. In this paper, the OCDMA system is designing using Multi Diagonal (MD) code and Direct Detection (DD) code to improve the Bit Error Rate (BER), Q-factor. The designed system is used to compare with the MD code and Modified Congruence Quadratic (MCQ) code to determine the performance improvement for multiple users.