To ensure the speed of logistics and customer service, a cross-border e-commerce logistics path optimization method based on Internet of Things (IoT) data fusion is studied. Select a typical IoT structure and deploy logistics path data collection nodes through this structure; Establish a cross-border e-commerce logistics path perception model based on the node characteristics of wireless sensors and the attenuation characteristics; Based on the perception model, obtain data, set priority indicators for cross-border e-commerce logistics paths, and determine the correlation of the indicators under the entropy method; Based on IoT data fusion technology and corresponding to different priority indicators, determine the optimization method of cross-border e-commerce logistics path based on IoT. Based on IoT data fusion technology, corresponding to different priority indicators, determine the optimization level of cross-border e-commerce logistics paths; Select constraint functions to divide the optimization hierarchy, combine the optimization objectives with fitness functions, determine the optimization order by solving the objectives, achieve the optimization of cross-border e-commerce logistics paths, and complete the design of the method. The experimental results indicate that this research method can effectively plan service cycles, shorten the time window for cross-border e-commerce logistics path planning, and ensure customer satisfaction.