In cross domain data anti-interference and high security optical quantum communication systems, the quantum key distribution process is susceptible to channel noise interference, leading to a decrease in key conversion rate. At the same time, quantum states undergo decoherence during long-distance transmission in single-mode optical fibers, making it difficult to ensure the security of quantum communication systems. Based on this, a design method for cross domain data anti-interference and high security optical quantum communication system integrating quantum key distribution is proposed. Build a three-layer architecture for optical quantum communication systems, namely the transmission layer, communication transmission layer, and reception layer. Generate secure keys through a quantum random number generator at the sending layer and distribute them, laying a secure foundation for subsequent communication; At the communication transmission layer, data is encrypted using distributed keys, and signal enhancement is achieved through optimized single-mode fiber transmission links in conjunction with quantum repeaters. At the same time, dynamic routing controllers are used to adjust the transmission path in real time and apply interference suppression algorithms to effectively overcome the effects of channel noise and quantum state decoherence; At the receiving layer, a high-sensitivity single photon detector accurately captures the quantum signal and, combined with a pre shared key quantum state demodulator, decrypts the ciphertext to obtain complete cross domain plaintext data, achieving high security and anti-interference optical quantum communication transmission. Performance testing was conducted on the design system, and the results showed that the median of the communication system was below the security threshold by 11% and the height range of the enclosure was relatively narrow, reflecting a low level of distribution error rate and the ability to maintain stable security. At the lowest signal-to-noise ratio, the error rate is only 3-4%. At the highest signal-to-noise ratio, the error rate drops below 1%, meeting the ideal standard, indicating that the system has strong anti-interference ability and high communication quality.