This paper is a record of forum between Sir Peter Hall, the Britain famous planning expert and Chinese youth planners. It is mainly about the origins, countermeasures and effect of planning system reform in Britain, and deeply illustrates the essence and logic of Britain planning system evolution. It also discusses the comparison of Chinese and British system and development stage, and explores the direction of future Chinese planning system reform. It provides cherished materials for understanding the process of British planning system and enlightenment for designing the new national land planning.