The Shinetsu Main Line (Japanese: 信越本線, Hepburn: Shin'etsu-honsen) is a railway line, consisting of three geographically separated sections, operated by the East Japan Railway Company (JR East) in Japan. It was originally one continuous line connecting Takasaki and Niigata via Nagano. Since the opening and later extension of the Hokuriku Shinkansen, sections running in parallel have either been discontinued or transferred to third-sector railway companies.
The name of the line refers to the old names for Nagano and Niigata prefectures, Shinano (Japanese: 信濃), and Echigo (Japanese: 越後).
