Abstract: The iron and steel industry is a major global emitter of greenhouse gases and atmospheric pollutants, and is a key sector for China to achieve its carbon peaking and carbon neutrality targets. Based on a comprehensive review of data and reports from the International Energy Agency, the World Steel Association and recent academic studies, this study compares the green and low-carbon transition pathways of major economies such as the European Union and the United States. Two typical models are summarized: (1) "Regulatory-driven + High carbon price + Hydrogen metallurgy/Carbon capture, utilization and storage (CCUS)" and (2) "Structural short-process advantages + Parallel demonstration of multiple technologies". Building on China's climate policy framework and large-scale ultra-low emission (ULE) retrofits in the steel sector, the study further synthesizes green and low-carbon technological pathways for China's steel sector, and their synergistic effects in pollution reduction and carbon mitigation. The technological pathways include five key areas: energy efficiency improvement and process energy conservation, short-process routes and circular resource use, clean energy substitution and hydrogen-based metallurgy, CCUS, and digitalization, intelligentization and lifecycle carbon management. The analysis indicates that ULE retrofits relying solely on end-of-pipe control may lead to "reducing pollution while increasing carbon". In contrast, integrating these retrofits with energy-efficiency measures, zero-venting and utilization of blast furnace gas, waste heat recovery, and higher scrap-EAF shares can generate significant air pollutant-carbon co-benefits. This study suggests that China should prioritize energy efficiency and structural adjustment in the near to medium term, while deploying hydrogen metallurgy and CCUS as strategic long-term options, supported by carbon pricing, green finance, an improved scrap system, low-carbon power supply and digital carbon management. Such an integrated approach is essential for steering the green and low-carbon transition of the steel industry in China and offers valuable insights for deep industrial decarbonization globally.