PROBLEM TO BE SOLVED: To discharge processing waste and the like without causing the processing waste to accumulate on a laser optical path when laser peening is performed on an inner surface of a pipeline.SOLUTION: According to an embodiment, a laser peening processing head 20 includes: a cylindrical member 30; a partition plate 35 which forms passages, such as an inflow passage 42 and an outflow passage 43, in an annular space formed at the inner side of an installation object pipeline 11 and the outer side of the cylindrical member 30; a passage water supply nozzle 36 which opens in the inflow passage 42; a laser radiation window 34 which opens in the outflow passage 43, allows water to flow therein, and transmits a laser beam; a laser transmission member 31; a light condensing member 32; and a deflection member 33.SELECTED DRAWING: Figure 1
展开▼