PROBLEM TO BE SOLVED: To provide an internal-processing layer forming method, an internal-processing layer forming member, and a surface three-dimensional structure member, which make it possible to acquire a workpiece of an intended surface shape without any trouble.SOLUTION: A condenser lens 72 for condensing a laser beam B is arranged in non-contact on an irradiated face 20t of a single crystal member 10. While a laser beam transmission distance from the condenser lens 72 to the irradiated face 20t is changed according to the irradiated position of the laser beam B on the irradiated face 20t, the laser beam B is focused inside of the single crystal member by the condenser lens 72, so that a layer of a three-dimensional structure dropped in a breaking strength is formed as a processing layer 21 inside of the single crystal member.
