[Objective] We study the landscape ecological risk in Tampa Bay watershed of America at temporal and spatial scale in order to provide scientific reference for exploitation, utilization and protection of Chinese harbor basin.[Methods] The TM/OLI remote sensing data in Tampa Bay watershed in 1985, 1995, 2005 and 2015 and the land use data were collected as the main data source, the landscape ecological risk evolution model was constructed, and the temporal and spatial characteristics of landscape pattern and ecological risk in Tampa Bay watershed was analyzed.[Results] (1) The area of artificial landscape was significantly larger than the area of natural landscape. (2) In 1985, the low and relative low ecological risk area accounted for 24.16% and 20.30%, respectively, in the Tampa Bay watershed. After 1995, the low and relative low ecological risk area was decreased, while the moderate ecological risk area was increased significantly. High and relative high ecological risk area was keep increasing until 2015. (3) During the last 30 years, about 3 210.84 km² of low ecological risk area was converted to high risk area, which accounted for 48.65% of the total area in the whole basin. The high ecological risk area expanded along the harbor side, and sporadic distributed in the mainland side of the Northeast area.[Conclusion] Impacted by human activities, the changes of landscape pattern and ecological risk in the Tampa Bay basin watershed was great during the past 30 years. The increasing rate of ecological risk level within the later 10 years was significantly lower than that at the initial 20 years. More attention has been paid on the protection and management of the ecological environment with the development and utilization of resources in the harbor.