Abstract: Building a scientific and reasonable ecological security pattern under climate change is a win-win way to achieve the sustainable development of regional socio-ecological composite system. This is of great significance to reduce climate risk and improve ecological stability. Taking Jiangsu Province as the study area, we identified the ecological source areas in terms of the suitability of ecological factors and the naturalness of ecosystems. The resistance surfaces were constructed, based on the relationship between the vulnerability to climate change and the ecological security pattern. The ecological corridors were identified using the least resistance model and the gravity model. The ecological security pattern were constructed and evaluated in Jiangsu Province, and an optimal restoration pathway was proposed. The results showed that the ecological source area of Jiangsu Province was 10,423.20km2, which accounted for 9.72% of the total land area of the province. The ecological source area was mainly distributed in rivers and lakes, coastal wetlands in the east and hilly and mountainous areas in the south-west. The vulnerability index to climate change ranged from 0.226-0.522, with a spatial pattern of ‘gradient-type elevation from the middle to the north of Jiangsu Province’, and the overall pattern was characterized by a ‘gradient-type elevation’. The vulnerability index demonstrated a spatial pattern of ‘gradient rising from central Jiangsu to southern Jiangsu and northern Jiangsu’. The overall vulnerability was low. The distribution of high vulnerability areas was mainly concentrated in the ecologically sensitive areas in hilly areas. A total of 35 ecological corridors with a total length of 2,448.66km had been extracted, which  presented a spatial pattern of ‘sparse in the north and dense in the south, and sparse in the east and dense in the west’. The overall ecological security pattern was ‘two vertical and four horizontal’. The ecological network was relatively imperfect, and the connectivity of ecological nodes was low. It was necessary to strengthen the construction of important ecological corridors. The study aimed to provide new perspectives for the construction of ecological security pattern and offer reference for the response to climate change to ensure regional ecological security