Abstract: Combined with the space information network architecture design requirements, a novel optimization design technology was proposed, which could achieve strongly network structure invulnerability. The natural connectivity was analyzed and selected as the invulnerability measure. In addition, a modified artificial immune algorithm was proposed based on the natural connectivity and the immune review. Results show that the proposed method improves the network invulnerability performance and provides a better robustness compared with typical space information systems in link failure mode and node failure mode.