<p>Electrochemical upcycling of captured CO₂ under high pressure holds significant potential to bridge between CO₂ emissions and hydrocarbon commodities, yet it remains underexplored. Here we convert gas-phase high-pressure captured CO₂ into ethylene (C₂H₄) using a high-pressure membrane electrode assembly equipped with In/Cu catalysts, affording up to 85% Faradaic efficiency and 750 mA cm⁻² partial current density under 20 bar. Theoretical calculations and operando studies link enhanced C–C coupling to the pressure-modulated *CO adsorption configuration and elevated CO₂ coverage. High pressure also mitigates salt precipitation by relocating bicarbonate formation to the catalyst–membrane interface, enabling stable electrolysis for over 1,500 h at 600 mA cm⁻². As a proof of concept, by recapturing residual CO₂, the system delivers industrial-grade 99.9% purity C₂H₄, creating an opportunity to turn the otherwise costly CO₂ capture into a profit. Energy analysis suggests that directly valorizing high-pressure captured CO₂, instead of depressurizing and repressurizing, is essential to minimize energy consumption.</p><p></p>