Abstract: Choosing Kenli County in the Yellow River Delta as the study area, using four TM digital images from 1987～2000, land use/cover information wasacquired by knowledge and rule based method, and land use/cover temporal and spatial changes were analyzed. Selecting environment vulnerable factors and establishing evaluation index system, the environment vulnerability of study area wasevaluated. After that, the effects of land use/cover and its changes on environment vulnerability were systematically analyzed by overlay, buffer and correlation analysis model. The results showed that the land use/cover in the study area from 1987 to 2000 changed obviously, especially the conversion among dry land, forest and grassland, salty wasteland and shoal land. The overall ecological environment was highly vulnerable and spatially regulated well. The environment vulnerability has close relationship with four land use/cover areas of forest and grassland, salty wasteland, water area, shoal land, and with the conversions of forest and grassland to dry land, salty wasteland, and salty wasteland to shoal land. Inaddition, land use/cover also has close relationship with the distances to the Yellow River and Bo Sea and the condition of soil and water environment. Our study was significant to quantitative study on land use/cover change and its environment effects in the environmental vulnerableregions.