Sustainable aviation fuel (SAF) is crucial for the aviation industry to achieve its 2050 net-zero emissions target. The energy consumption, environmental impacts, and economic costs of SAF vary significantly due to feedstocks and processes. This study applies life cycle assessment to evaluate SAF routes’ energy-environment-economy (3E) performance; uses the STIRPAT model to quantify key factors influencing aviation emissions; and then integrates 3E indicators of SAF and factors affecting aviation emissions into a system dynamics model simulating impacts of SAF routes and blending ratios on aviation emissions. The results show that: different SAF routes have their advantages in terms of 3E; reducing aviation demand and improving aircraft fuel efficiency are the key emission reduction levers; and under the set scenario of blending ratios of SAF and conventional jet fuel in 2050, only blending 85 % and 100 % SAF can achieve the 65 % carbon emission reduction target required by the aviation industry.