To clarify the evolution process of ecological security pattern and its driving factors in the Pearl River Delta (PRD) from 1986 to 2019,ecological source area was identified based on the remote sensing ecological index (RSEI), ecological resistance was evaluated by integrating the natural, social and economic factors, ecological networks were constructed by using the minimum cumulative resistance (MCR) model and the landscape connectivity. The results show that: (1) The mean values of RSEI in 1986, 2003 and 2019 were 0.78, 0.84 and 0.74 respectively, which indicated an increasing trend at first and then a decreasing trend. While the mean value of ecological resistance continued to increase by 9.49%. The spatial differentiation of ecological quality and resistance both intensified.(2) The ecological connectivity changed dynamically with the evolution of landscape patterns. The spatial distribution of important ecological nodes and corridors has gradually developed from concentrated in the East region in 1986 to a semi ring distribution around the PRD in 2019.(3) Climate change, rapid urbanization and ecological management are the main factors affecting the evolution of ecological security pattern in the PRD. The warm and humid trend of climate change was an important reason for the ecological improvement from 1986 to 2003. The negative impact of construction land expansion on ecological security gradually appeared from 2003 to 2019. The implementation of ecological policies such as “Afforestation on Wasteland” and “Grain for Green” had an important impact on the evolution of ecological security pattern.

ecological security pattern；remote sensing ecological index (RSEI)；ecological network；landscape function； the Pearl River Delta