Abstract:Islet in river of city is a new type of recreation space and it is significant to discuss the structure of its vulnerable ecosystem and evaluate its recreation ecological security. Based on the theory of systems ecology and model of PSR, the paper constructed evaluation index system of recreation ecological security for islet in river of city. The system included three subsystems (core region of islet, buffer region of river, influence region of city) and three factors (pressure, state, response). Taking the Dongzhou Islet in Hengyang city, Hunan province as an example, the empirical study was conducted in the paper. The results show that the degree of recreation ecological security for islet in river of city is low and the different subsystems have differentiated characters: the degree of recreation ecological security for core region of islet is lowest, its recreation ecological security problems were most prominent and most indicators in this region are the important influencing factors of ecological security; the degrees of recreation ecological security for buffer region of river and influence region of city were higher, but some factors in the regions had negative effect on recreation ecological security of islet in river of city, .