<p>A decompressor capable of suppressing the disturbance of the flow of a refrigerant. The decompressor (1) comprises a columnar part (3) and a cylindrical part (2). The cylindrical part (2) is disposed on the outside of the columnar part (3). A spiral flow passage (7), intermediate area flow passages (5), and large area flow passages (6) are formed in the decompressor (1). The spiral flow passage (7) is positioned between a spiral groove formed in one of the columnar part (3) and the cylindrical part (2) and the peripheral surface of the other. The intermediate area flow passages (5) are adjacent to the spiral flow passage (7) and have a larger flow passage area than the spiral flow passage (7). The large area flow passages (6) are disposed on the opposite side of the spiral flow passage (7) through the intermediate area flow passages (5). The large area flow passages (6) have a larger flow passage area than the intermediate area flow passages (5).</p>
