A fluid sterilization apparatus is provided with: a light source that has a semiconductor light-emitting element that emits ultraviolet light and a flow passage that is formed so as to allow a fluid subject to sterilization to pass through and allow the fluid to be irradiated with ultraviolet light. The flow passage is formed such that the flowing direction of the fluid changes in a plane that faces a light-emitting surface of the semiconductor light-emitting element.
