<p>Rapid urbanization has heightened the vulnerability of ecosystems, endangered urban ecological security, and hampered sustainable socio-economic development. To address this issue, this study uses Jiangsu Province, a typical quickly developing province in China, as a case to examine the evolution trend and influential factors of the regional ecological security pattern. Specifically, the evaluation index system of ecological security pattern in Jiangsu Province was built using the composite ecosystem theory and the pressure-state-response (PSR) model, and the spatial and temporal evolution trends of ecological security pattern was evaluated through Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) and gray correlation analysis. Finally, the major influencing factors were identified by the principal component analysis. The results are as follows. (1) From 2008 to 2020, the ecological security level in Jiangsu Province fluctuated, with an overall higher trend, and it falls between the sensitive and critical security levels. (2) The ecological security pattern in Jiangsu Province has a diverse spatial distribution, with “high in the north and low in the south”. (3) Urbanization, ecological pathology degree, population pressure and atmospheric environmental pressure all have a negative correlation with regional ecological security, with industrial pollution emissions and treatment having the biggest impact. The findings provide effective scientific reference for assessing and managing regional ecological security trends.</p>