The polder field was an important form of land use in the West Lake area of ancient Hangzhou. The development of polder fields not only brought crisis to West Lake, but also provided opportunities for its later transformation from production facilities to ornamental landscapes. Based on a large amount of historical literature, this paper studies the development and evolution of water conservancy landscapes in Western Zhejiang under the background of polder fields, and comprehensively examines the process and characteristics of the construction of West Lake scenery in the Song Dynasty. On this basis, the influence of the tradition of polder fields on the construction of the West Lake landscape in the Song Dynasty was specifically explored. It was believed that the development of the polder field system promoted the establishment of the “field city lake” relationship in Hangzhou, and promoted the construction of water conservancy facilities in the West Lake during the Song Dynasty. Later, through the integration of the West Lake landscape by officials and civilians, polder fields were promoted to be expressed as aesthetic elements in the construction of the West Lake landscape, transforming the West Lake from a non-scenic suburban water body to a public landscape with ornamental value. The following three conclusions are drawn: (1) The governance of polder fields ran through the overall process of the construction of West Lake scenery in the Song Dynasty; (2) The characteristics and forms of polder fields based on water conservancy functions became the landscape genes for the construction of the West Lake landscape in the Song Dynasty; (3) The game and choice between polders and scenery made the Song Dynasty a crucial period for the transformation of West Lake in Hangzhou from a natural landscape to a cultural landscape.