Abstract: As the only scalable low-carbon alternative fuel for aviation, the technical maturity, economic viability, policy adaptability, and environmental impacts of Sustainable Aviation Fuel （SAF） have become core factors for industrial implementation. Based on the current development status and publicly available industry data, the authors systematically sort out the characteristics of SAF feedstocks, the principles and maturity differences of production technology routes, comprehensively interpret the global policy framework （international CORSIA mechanism, EU ReFuelEU, US Inflation Reduction Act （IRA）, and China’s pilot policies）, analyze the core factors restricting economic viability, and quantify its carbon footprint （emission reduction rate of 50%–92%） combined with Well-to-Wake （WtW） life cycle assessment. In terms of technical routes, the hydroprocessed esters and fatty acids （HEFA） technology, featuring high technical maturity and relatively stable feedstock supply, currently accounts for approximately 80% of the global sustainable aviation fuel （SAF） production volume, making it the most feasible industrialization pathway in the short term. In contrast, the Fischer-Tropsch process（FT） and Power-to-Liquid （PtL） technologies, despite their high current costs and lack of large-scale commercialization, are widely recognized as key development directions in the medium to long term due to their superior feedstock adaptability and greater emission reduction potential. At the policy level, the global primary SAF incentive framework is jointly constituted by the Carbon Offsetting and Reduction Scheme for International Aviation （CORSIA） launched by the International Civil Aviation Organization （ICAO）, the ReFuelEU Aviation regulation implemented by the European Union, the tax incentive provisions under the U.S. Inflation Reduction Act （IRA）, and regional pilot policies in China. Among these, the EU’s mandatory blending mandate and the U.S. tax credit policy have demonstrated remarkable effectiveness in driving capacity construction and downstream application of SAF. Economic analysis indicates that policy subsidies can reduce the production cost of the HEFA route by 30%–40%, with its price projected to drop to within 1.5 times that of conventional jet fuel by 2030. For China, it is imperative to strengthen the supply chain construction of sustainable feedstocks such as waste oils and biomass, and establish a multi-tiered incentive mechanism based on carbon pricing, fiscal subsidies, and green finance, thereby systematically promoting the healthy, orderly, and large-scale development of the domestic SAF industry.