The plant-soil feedback theory originates from the traditional agriculture. In recent years, it has become an important theory and methodological support in ecology for studying the vegetation dynamics, community composition and functions, and the terrestrial ecosystems responding to human interferences and climate changes. We first introduced the definitions, types and mechanisms of plant-soil feedback. Then, we reviewed how this theory could be used in natural ecosystems to understand the fundamental ecological questions including plants invasion, succession, maintenance of species coexistence and diversity, plant diversity-productivity relationships, trophic interactions and responses to climate changes. Moreover, we extended plant-soil feedback feedback theory into agricultural ecosystems, and introduced the advances and application potentials based on the theory to obtain more productivity in diverse cropping systems, soil remediation, and cropping systems design, etc.. Finally, the future research directions of plant-soil theory in future development were proposed, with a view to fully understand and utilize the plant-soil feedback to promote ecosystem services and functions and sustainable development in both natural and agricultural ecosystems.