A liquid separation constituent is used by covering a first element portion having a fiber layer for separating liquid from gas discharged from a compressor, and includes a second element portion, a holding portion, and a non-element portion. The second element portion is a tubular portion having a fiber layer that is disposed on the outer side in the radial direction so as to surround the first element portion when the second element portion covers the first element portion and further separates liquid from gas separated by the first element portion. The holding portion is a portion that holds the second element portion such that a gap is formed between the first element portion and the second element portion in the radial direction. The non-element portion is a portion configured to suppress liquid seeping out from a lower portion of the first element portion from scattering to the second element portion.