To increase pressure resistance of a connection state between a flow path member and a connection member.SOLUTION: The fluid sterilizing apparatus of the embodiment includes a flow path member having a first flow path for flowing a fluid, a flow path member having a first flow path, a second flow path, A light source that irradiates ultraviolet rays into the first flow path, a second flow path connected to one end of the flow path member and provided with a light source, and communicating with the first flow path is disposed around the light source A second connecting member connected to the other end of the flow path member, and a connecting member connecting the first connecting member and the second connecting member.(FIG.【課題】流路部材と接続部材との接続状態の耐圧性を高める。【解決手段】実施例の流体殺菌装置は、流体を流すための第1の流路を有する流路部材と、第1の流路の、流体の流れ方向に交差する流路断面に対向して配置され、第1の流路内へ紫外線を照射する光源と、流路部材の一端に接続されると共に光源が設けられ、第1の流路に連通する第2の流路を光源の周囲に有する第1の接続部材と、流路部材の他端に接続された第2の接続部材と、第1の接続部材と第2の接続部材とを連結する連結部材と、を備える。【選択図】図2
