An optical processing nozzle comprising: a beam path that is arranged to allow a beam emitted by a light source to pass through the beam path toward a processing surface; and a channel structure that is arranged around the beam path and is configured to eject a fluid toward the processing surface, wherein the channel structure includes: a first channel layer including a first inflow port through which the fluid flows, at least two first passage holes through which the fluid flowing from the first inflow port passes, and a first channel that guides the fluid from the first inflow port to the first passage holes; and a second channel layer including at least two second inflow ports through which the fluid flows from the first passage holes, at least four second passage holes through which the fluid flowing from the at least second inflow port passes, and a second channel that guides the fluid from the at least two second inflow ports to the at least four second passage holes, an ejection port from which the fluid having passed through the at least four second passage holes is ejected toward the processing surface, the at least two first passage holes are arranged such that, when the at least two first passage holes are rotated about an inflow axis that passes through the center of the first inflow port and extends in the inflow direction of the fluid in the first inflow port, one of the first passage holes coincides with the other of the first passage holes at a rotation angle of smaller than 360°, for each of the at least two second inflow ports at least one respective combination of the at least four second passage holes is arranged such that, when the second passage holes of the respective combination are rotated about a respective inflow axis that passes through the center of the respective second inflow port and extends in the inflow direction of the fluid in the respective second inflow port, one of the second passage holes of the respective combination coincides with another of the second passage holes of the respective combination at a rotation angle of smaller than 360°, and the ejection port is arranged such that, when the ejection port is rotated about the optical axis, the ejection port is coincident at a rotation angle of smaller than 360°. a beam path that is arranged to allow a beam emitted by a light source to pass through the beam path toward a processing surface; and a channel structure that is arranged around the beam path and is configured to eject a fluid toward the processing surface, wherein the channel structure includes: a first channel layer including a first inflow port through which the fluid flows, at least two first passage holes through which the fluid flowing from the first inflow port passes, and a first channel that guides the fluid from the first inflow port to the first passage holes; and a second channel layer including at least two second inflow ports through which the fluid flows from the first passage holes, at least four second passage holes through which the fluid flowing from the at least second inflow port passes, and a second channel that guides the fluid from the at least two second inflow ports to the at least four second passage holes, a first channel layer including a first inflow port through which the fluid flows, at least two first passage holes through which the fluid flowing from the first inflow port passes, and a first channel that guides the fluid from the first inflow port to the first passage holes; and a second channel layer including at least two second inflow ports through which the fluid flows from the first passage holes, at least four second passage holes through which the fluid flowing from the at least second inflow port passes, and a second channel that guides the fluid from the at least two second inflow ports to the at least four second passage holes, an ejection port from which the fluid having passed through the at least four second passage holes is ejected toward the processing surface, the at least two first passage holes are arranged such that, when the at least two first passage holes are rotated about an inflow axis that passes through the center of the first inflow port and extends in the inflow direction of the fluid in the first inflow port, one of the first passage holes coincides with the other of the first passage holes at a rotation angle of smaller than 360°, for each of the at least two second inflow ports at least one respective combination of the at least four second passage holes is arranged such that, when the second passage holes of the respective combination are rotated about a respective inflow axis that passes through the center of the respective second inflow port and extends in the inflow direction of the fluid in the respective second inflow port, one of the second passage holes of the respective combination coincides with another of the second passage holes of the respective combination at a rotation angle of smaller than 360°, and the ejection port is arranged such that, when the ejection port is rotated about the optical axis, the ejection port is coincident at a rotation angle of smaller than 360°.