To provide a film body part reforming device which can easily and efficiently make reforming treatment operation of the film body part to be treated when a large-sized device is manufactured.

This film body part reforming device comprises a light source 10, an optical path moving means 3 which forms a light beam 20 emitted from the light source 10 to a desired shape and orients the shaped light beam 20 to a desired direction and a substrate moving means 1 which is mounted with a substrate 4 including the film body part 2 to be treated and is capable of moving the film body part 2 to be treated so as to make its prescribed part 30 correspondent to the optical path. The film body part reforming device 100 described above is so constituted that the operating accuracy of the optical path moving means 3 is made higher than the operating accuracy of the substrate moving means 1.