Although urban fringe is regarded as a unified academic concept, the actual development results present a strong divergence into two categories: the strongsided urban fringe and the weak-sided urban fringe. This paper starts from basic concept of the weak-sided urban fringe based on existing theory and summarizes the features of the weak-sided urban fringe according to empirical cases, including the low-quality, collage-style land use mode, the structural shortage of both core resources and fundamental facilities, and the fragmented spatial governance. Secondly, differing from the development of strong-sided urban fringe with high investment, urban sprawl and self-replication dominated by growth machines during the rapid urbanization period, this paper proposes the weak-sided urban fringe should adopt a flexible planning approach characterized by precise input, structural optimization and organic growth. Finally, taking the example of Strategic Plan of Yuhuatai District,this paper initially discusses the methodology of flexible planning, including repair of embedded structures, action-oriented organic regeneration and the organizational optimization of multi-governance systems guided by planning.