<p>Non-carbon dioxide (non-CO₂) greenhouse gas (GHG) emissions are a significant contributor to climate change. However, the exploration of non-CO₂ GHG emissions reduction remains limited. Based on structural path analysis and scenario analysis, this study develops an indicator to identify critical sectors within key inter- and intra-regional supply chains and reveals the mitigation potential of methane (CH₄), nitrous oxide (N₂O), and fluorinated gases. The results show that for key inter-regional supply chains, non-CO₂ GHG emissions driven by the US and the EU rose 57% from 1990 to 2022. In 2022, the petrochemical and food sectors in the US and the EU dominated embodied CH₄ and N₂O emissions in inter-regional supply chains, driving more than 147 MtCO₂-eq of CH₄ emissions from mining sectors in Russia and the Middle East (an increase of 42% compared with 1990), and 12 MtCO₂-eq of agricultural N₂O emissions from Sub-Saharan Africa and Other America (an increase of 118% compared with 1990). The critical sectors in intra-regional supply chains were concentrated in China (mining, manufacturing, petrochemical, and construction sectors) and India (agriculture sector). Considering the supply chain linkages of critical sectors in the US, the EU, China, and India, the mitigation potential of non-CO₂ GHG emissions could reach 2,754 MtCO₂-eq, which is 1.4 times that of only adopting production-side measures. Thus, to enhance multi-sector efforts in reducing non-CO₂ GHG emissions, the US and EU are encouraged to provide more funds and technologies to developing regions such as Sub-Saharan Africa.</p>