Multimodal transportation systems play a pivotal role in enabling the flow of goods across different regions. Traditional models used in the prediction of route selection often overlook cost factors, leading to elevated costs of multimodal transportation route selection. This research examines a multimodal transportation route selection model that takes into account the optimization of transportation costs. In order to ascertain the practicability of the model, we put it to the test using a set of example problems. The process of tackling these problems not only allowed us to verify the model’s effectiveness but also highlighted its potential in real-world applications. Our analysis revealed that the model could indeed identify the most cost-effective routes for multimodal transportation. In conclusion, this study underscores the importance of considering transportation costs when selecting routes in multimodal transportation. It further proposes ways to optimize these costs, such as the fortification of logistics systems, the application of information technology, and the strengthening of standard systems. Our findings can significantly contribute to improving the efficiency of multimodal transportation.