By making use of the needle method, the coating design of green He-Ne laser with internal cavity and the spectrum performance of the designed coating are introduced. The newly designed films of green He-Ne laser have been coated by making use of ion beam sputtering deposition, and the measured results have been given out. Many types of green He-Ne laser with internal cavity have been fabricated and the related techniques have been discussed. In these green He-Ne lasers, the lasers with cavity length of 420 mm have typical output power of 3 mW (single mode), the lasers of 360 mm have typical output power of 2 mW (single mode), the lasers of 240 mm have typical output power of 1 mW (single mode), and the small and short lasers with cavity length of 100 mm have also typical output power of 0.1 mW.