A gas circulation engine includes a combustion chamber to which high-pressure fuel in a first high-pressure fuel supply passage, an oxidant and working gas are supplied; a circulation path that connects an intake-side portion and an exhaust-side portion of the combustion chamber to each other; a fuel bleed-off tank into which the high-pressure fuel in the first high-pressure fuel supply passage is bled off; a fuel bleed-off valve that permits or shuts off communication between the first high-pressure fuel supply passage and the fuel bleed-off tank; and a fuel bleed-off control unit that permits communication between the first high-pressure fuel supply passage and the fuel bleed-off tank by opening the fuel bleed-off valve when the engine is stopped, the communication between the first high-pressure fuel supply passage and the fuel bleed-off tank being shut off during operation of the engine.