The paper conducts a simulation analysis of passive optical network based on the Optical Code Division Multiple Access technology. Optical Code Division Multiple Access (OCDMA) Passive Optical Networks (PON) system provides a major improvement over TDM-PON, WDM-PON systems and thus help in improving the overall performance of the PON system. The system is simulated for 10Gbps using 2 codes, Modified Quadratic Congruence codes with a complementary detection scheme and Multi-Diagonal codes with a direct detection scheme. The variation in the results are analyzed when the fiber length is varied for 10kms, 50kms, 80kms and 100kms and higher. The simulation is carried out using Optisystem 13. It has been observed that the system performs well while using Multi-Diagonal Codes for distances up to 140kms. © Research India Publications.