Master Plan of Greenery: Master plan, conducted by municipalities, aim for conservation of green space and promotion of greening. It will be published by municipalities after reflected the opinions of residents (Article 4 of Urban Green Space Law). Background: Recently, global warming and the heat island phenomenon are urgent issue. There are various ways to achieve the low carbon society. One of them is land management. Objectives: To analyze from two ways of the park vegetation survey and GIS data in Hiroshima city. To estimate of the future green spaces, the previous data in the reports by Moriguchi(2000) and Nakagoshi(2006) were compared with current one. Study site: The area is classified the delta urban green space zone by Master Plan of Greenary. Method: Vegetation survey in the same parks in the literature (Nakagoshi 2006). Investigate tree species and their diameter at breast height (DBH), and tree height more than 1.3m in height. Result: 161 parks out of the 197 parks were investigated. There are 7,750 trees belonging 125 species. The positive relationship between the size of the parks and the number of the trees was observed.