This paper used HEC-HMS hydrological model and statistical analysis method to examine the relationship between flood eigenvalues (i.e. flood volume, peak flow) and landscape pattern indexes of different landscapes. And on the basis of the above relationships, this paper constructed a flood ecological risk index to quantitatively calculate the basin's flood-landscape ecological risk. Then, the spatio-temporal risk change analysis of the whole basin and comparative risk analysis between selected sub-basins were performed. The Qinhuai River basin was selected as the study area, and two historical landscape distributions (2003 and 2017) were used in this study. The results showed that, for different landscapes, there are certain relationships between landscape patterns and flood eigenvalues, for different landscapes, the response indexes and degrees are different. From 2003 to 2017, the flood-landscape ecological risk increased and showed significant spatial differences. Landscape patterns have significant impacts on regional floods. In urbanization process, avoiding forming large-scale landscape patches, increasing landscape abundance of landscapes, and increasing contact area between different types of landscape patches can be helpful to reduce the negative effects of the increase of urban landscape area on flood.