Economic integration and market competition make scientific and refined supply chain management become particularly important. The optimization of location and layout of logistics nodes in closed supply chain is the key to improve supply chain efficiency and reduce cost. Based on the spatial-temporal network model, this paper discusses the optimization of supply chain node location and layout in dynamic and complex economic systems. By constructing the model, combining the actual logistics data and using the advanced optimization algorithm, this study puts forward a new optimization method of logistics node location and layout. This paper introduces the construction process of spatiotemporal network model in detail, including data collection, model hypothesis, establishment of objective function and formulation of constraint conditions. Meanwhile, this paper introduces the genetic optimization algorithm, and explains the implementation steps and parameter Settings of the algorithm. The final conclusion shows the effectiveness of the optimization model, pointing out that by implementing the optimization strategy, the maximum logistics cost is only $1164, the maximum inventory turnover rate is 94% and the maximum delivery punctuality rate is 18%, thus enhancing the competitiveness of the supply chain.