To provide a dewatering apparatus for a water jet loom, for improving the dewatering efficiency on the upper surface side of a woven fabric.

The dewatering apparatus has the following construction: a woven fabric path M2 between a lower side suction cylinder 12 and a 1st press roller 13 is downwardly sloped from a lower side suction cylinder 12 side toward the 1st press roller 13 side. The woven fabric path M2, an upper side suction cylinder 17 is set. The lower side suction cylinder 12 is cylindrical and the upper side suction cylinder 17 is of quadrangular pipe shape. The lower side suction cylinder 12 is made in contact with the underside of a woven fabric W. The contact plane 171 of the upper side suction cylinder 17 is made in contact with the upper surface of the woven fabric W at the path M2. Suction slits 121 and 172 are provided on the lower side suction cylinder 12 and the upper side suction cylinder 17 respectively, wherein the suction slit 121 is provided on the upper side of the lower side suction cylinder 12 and the suction slit 172 is provided on the contact plane 171.