Taking the "Unicorn Island Park Project" of Zaha Office in Chengdu as an example, aiming at the local overhead platform space of large complex, the safety evacuation situation of personnel in case of fire in emergency is analyzed, and the corresponding emergency evacuation optimization strategy is proposed. This paper first introduces the relevant project overview and fire protection design to provide reference and analysis basis for simulation. Secondly, based on the pathfinder evacuation simulation software, it conducts evacuation simulation research on the space above and below the large platform in Unicorn Island Park, determines the basic personnel composition and characteristic parameters through investigation, analyzes the evacuation efficiency and congestion situation in case of fire, and summarizes the evacuation problems existing at the junction between the monomer and the large platform. Finally, aiming at the existing problems, it puts forward corresponding optimization strategies to improve evacuation efficiency. This study can provide a reference for the optimization and safety management of evacuation problems in crowded places of large complex overhead platforms.