To provide a fluid sterilization module, in which the variation in flow rate of the object in the processing flow path due to assembly error, etc. is suppressed.SOLUTION: The fluid sterilization module comprises: an inner cylinder 21 forming a processing flow path 21d； an inflow side rectification chamber 26 communicating with the processing flow path 21d through an opening on one end side of the inner cylinder 21； an inflow part 4 for flowing an object into the inflow side rectification chamber 26； an outflow side rectification chamber 27 provided along the outer peripheral surface of the other end side of the inner cylinder 21； a communication port 21a provided in the inner cylinder 21 and communicates the processing flow path 21d and the outflow side rectification chamber 27； an outflow part 5 for flowing out the object from the outflow side rectification chamber 27； a light-emitting element 34a provided facing the opening on the other end side of the inner cylinder 21 and irradiating ultraviolet light toward the object that passes through the processing flow path 21d； and a window part 31 provided between the end face on the other end side of the inner cylinder 21 and the light emitting element 34a and closing the entire opening on the other end side and in which at least a region facing the irradiation surface of the light emitting element 34a is formed of an ultraviolet transmitting material, and in which the object in the processing flow path 21d flows into the outflow side rectification chamber 27 only through the communication port 21a.SELECTED DRAWING: Figure 2【課題】組み付け誤差等により処理流路内で対象物の流速がばらつくことを抑制する。【解決手段】処理流路２１ｄを形成する内筒２１と、内筒２１の一端側の開口部を介して処理流路２１ｄと連通する流入側整流室２６と、流入側整流室２６に対象物を流入する流入部４と、内筒２１の他端側の外周面に沿って設けられた流出側整流室２７と、内筒２１に設けられ処理流路２１ｄと流出側整流室２７を連通する連通口２１ａと、流出側整流室２７から対象物を流出させる流出部５と、内筒２１の他端側の開口部に面して設けられ、処理流路２１ｄを通過する対象物に向けて紫外光を照射する発光素子３４ａと、内筒２１の他端側の端面と発光素子３４ａとの間に設けられ他端側の開口部全体を塞ぎ、少なくとも発光素子３４ａの照射面と対向する領域が紫外線透過材料で形成された窓部３１とを備え、処理流路２１ｄ内の対象物は連通口２１ａのみを介して流出側整流室２７に流入する。
