<p>To address the issues of incomplete optimization and low efficiency in existing models for architectural spatial layout optimization, this study proposes an innovative Two-Stage Dual-population Particle Swarm Optimization model to optimize the architectural spatial layout in old communities. The study begins by formulating an objective function based on the requirements of elderly residents and specifying the associated constraints. Then, it applies the Two-Stage Dual-population Particle Swarm Optimization model to search for the optimal layout solution. The experimental results show that in terms of practical application effectiveness, the optimized area ratio of the proposed model is 3.24%. Despite this low optimization area ratio, the safety risk reduction rate in the elderly-friendly area reaches 72.47%, while the coverage rate of accessible facilities reaches 95.04%, significantly outperforming the three comparative models. The above results indicate that the model has significant application value in optimizing the spatial layout of aging friendly micro renewal buildings in old communities. At the theoretical level, this study has broken through the limitations of traditional optimization models and provided a more efficient and accurate technical path for optimizing architectural spatial layout. At the practical level, the results can directly assist in the age-friendly renovation of old communities, effectively improving the living quality and safety of the elderly population.</p>