Abstract: 【Objective】This study on the dynamics of urban tree structures and their affecting factors is important for urban greening and urban tree management in the process of urban renewal. 【Method】 Based on the tree survey data of the Nanjing City area respectively in 1999 and 2015, the change in tree structure and performance in the rapidly renewing residential area was studied via investigating into the species composition, morphology, and health conditions, and their affecting factors were analyzed. 【Result】The abundance of Ligustrum incidum, a native tree species, ranked the largest over the 15 years, while the abundances of Acer buergerianum, Prunus persica, Magnolia denudata, Paulownia fortunei and some other native tree species dropped drastically out of the top 20. Residents' preferences, environmental benefits, and the economical market were the dominant factors driving the changes in species composition and configuration, while urban reconstruction also influenced the changes to some extent. The limited space greatly restricted tree form development in the built environment, leading to the average crown size dropping by 14.6%.【Conclusion】 A lack of tree maintenance and residents' adverse behavior accounted for a decline in the health of residential trees in recent years. Suggestions for improvement included adjusting tree species composition, forbidding the random pruning of trees, and strengthening the greening of reconstructed land.