To provide a liquefied gas processing system for compactly and efficiently processing surplus gasified liquefied gas.

This liquefied gas processing system includes: a compression means 2 for compressing outside air; a pressure type combustion means 6 having a furnace 3 for burning the gasified liquefied gas and combustion air introduced from a storage tank by guiding the compressed outside air as jacket air and the combustion air, and a jacket part 5 for covering the periphery of a furnace wall 4 that forms the furnace 3 and guiding the jacket air; high-pressure-side steam generating means 7 and 8 for generating steam by exchanging heat with the combustion gas derived from the pressure type combustion means 6; a steam turbine 9 for guiding the steam generated in the high-pressure-side steam generating means 7 and 8; and a gas turbine 12 arranged coaxially with the compression means 2 and driven by combustion gas guided from the high-pressure-side steam generating means 7 and 8.