Urban spatial expansion is an important driving force for land cover morphological changes. The impact of local urban expansion can extend to the regional level, and result in local and even regionally ecological environment changes. Taking a part of the southeast coastal area in Fujian Province (including Xiamen, Quanzhou and Zhangzhou, Min-Delta region for short) as an example, GIS and statistical analysis method was used to analyze the impact of urban expansion process on the ecological security pattern, especially the evolution of forest-water pattern, and the difference on different scale was compared. The results showed that: ① urban expansion process was closely related to the evolution characteristics of the ecological security pattern. ② Urban expansion process had a significant impact on the regionally ecological security pattern succession. The impact of different stages of urban expansion on the regionally ecological security pattern was significantly different, mainly reflected by the Largest Patch Iindex and Patch Aggregation Degree. ③ The landscape indices showed different performances in this process, among which Patch Ratio was the main response index of regional forest water pattern evolution during local urban expansion process, and Landscape Shape Index was the only one showing scale effect. The results can provide theoretical references for optimizing regional ecological security pattern, and contribute to rational planning and management of urban expansion.