This study interviewed five practical experts with experience in this field to jointly explore the principles and challenges of integrating expeditionary learning into the USR extended courses in the universities. The results of the study also identify with that expeditionary learning is an educational model that emphasizes interdisciplinary learning, requires goal-oriented and thematic curriculum design, needs to arouse the learners' motivation and enthusiasm, requires a practical field environment, and needs a connection with the community industry. In the process of introduction and implementation, the teachers need to have a high degree of enthusiasm for education, truly understand the core of expeditionary learning, and have the mental competency of continuous interdisciplinary learning. Meanwhile, this paper synthesizes three typical successful cases of American expeditionary learning. The author hopes that this paper can be a reference to the teachers who are implementing the USR extended courses.