The Shinonoi Line (篠ノ井線, Shinonoi-sen) is a railway line in Nagano Prefecture, Japan, operated by the East Japan Railway Company (JR East). It connects Shinonoi Station in Nagano with Shiojiri Station in Shiojiri.
The line is a corridor between the Shinetsu Main Line and the Chūō Main Line. All the limited express trains on the Shinonoi Line come from the Chūō Main Line: Azusa from Tokyo and Shinano from Nagoya.