The present invention relates to a vessel including a system which can demonstrate an improved evaporated gas re-liquefying performance compared to a conventional partial re-liquefying system, and the vessel comprises: a storage tank storing liquefied gas; an evaporated gas heat exchanger which heat exchanges and then cools first fluid; a compressor which compresses a portion of evaporated gas; an extra compressor which compresses the other portion of the evaporated gas; a propulsion compressor which compresses the first fluid; a refrigerant heat exchanger which additionally cools the first fluid; a refrigerant decompressor which expands a second fluid and then returns the second fluid to the refrigerant heat exchanger; and a first decompressor which expands the first fluid cooled by the evaporated gas heat exchanger and the refrigerant heat exchanger.
