The East Garden of Tianyige Graden is located in the southeast corner of whole garden in Ningbo. It was founded in 1959, and sometimes called “External Garden ”or “Big Garden”. Later, under Chen Congzhou's planning and guidance, ponds were dug to pile hills and trees and bamboo were planted. Finally, the East Garden was built and opened to the public in1986. Based on the analysis of archives and the interview with the senior designers, the construction process of East Garden are reviewed and summarized. Also, the landscape layout and construction method of the East Garden were comprehensively analyzed. This paper puts forward a glimpse of Chen Congzhou’s gardening theory and preservation principles of cultural relics and provides some advices to current cultural relics protection work.