Abstract: To promote the standardization and scaling of the forest–medicinal plant intercropping system, enhance the yield and quality of medicinal materials, and support the coordinated ecological and economic development in mountainous areas, this study systematically reviews the understory intercropping techniques for four medicinal plants: Paris polyphylla, Polygonatum cyrtonema, Ganoderma lucidum, and Dendrobium officinale. The review covers technical requirements such as terminology and definitions, production environment, cultivation techniques, field management, pest and disease control, harvesting, and processing. By integrating and optimizing the ecological habits, growth cycles, and management measures of these four medicinal species, the efficient utilization of forest understory space and the synergistic improvement of medicinal material quality are achieved.