Disclosed is a fuel gas supply system. According to one embodiment of the present invention, the fuel gas supply system comprises: a heat exchange unit for receiving evaporated gas of liquefied gas from a storage tank, and performing heat exchange; a fuel compression unit for compressing heat-exchanged evaporated gas in accordance with the required pressure of a demand source; a re-liquefying unit for re-liquefying at least a portion of the compressed evaporated gas; and a fuel supply line for connecting the storage tank, the heat exchange unit, the fuel compression unit, and the demand source. The re-liquefying unit of the present invention comprises: a rear end compression unit for compressing evaporated gas passing through the fuel compression unit; and an expander for expanding the compressed evaporated gas in which the temperature is lowered by exchanging heat with the evaporated gas supplied from the storage tank by the heat exchange unit after passing through the rear end compression unit. A re-liquefying line branched from the rear end of the fuel compression unit of the fuel supply line, and connecting the rear end compression unit, the heat exchange unit, the expander, and the storage tank is provided. According to the present invention, power consumed during re-liquefaction of evacuated gas can be minimized.

연료가스 공급시스템을 개시한다. 본 발명의 실시 예에 따른 연료가스 공급시스템은 저장탱크로부터 액화가스의 증발가스를 공급받아 열교환시키는 열교환부; 열교환된 증발가스를 수요처의 요구압력에 따라 압축시키는 연료압축부; 압축된 증발가스 중 적어도 일부를 재액화하는 재액화부; 및 저장탱크, 열교환부, 연료압축부 및 수요처를 연결하는 연료공급라인; 을 포함하되, 재액화부는 연료압축부를 통과한 증발가스를 압축시키는 후단압축부와, 후단압축부를 통과한 후, 열교환부에 의해 저장탱크로부터 공급된 증발가스와 열교환되어 온도가 낮아진 압축된 증발가스를 팽창시키는 팽창기를 포함하고, 연료공급라인의 연료압축부 후단으로부터 분기되어, 후단압축부, 열교환부, 팽창기 및 저장탱크를 연결하는 재액화라인을 마련한다.