S57 may refer to: S57 (Long Island bus) S57 (New York City bus) serving Staten Island , a submarine of the Royal Australian Navy , a submarine of the Indian Navy Prince Skyline (S57), a Japanese automobile S57: Use appropriate containment to avoid environmental contamination, a safety phrase Savoia-Marchetti S.57, an Italian flying boat Sikorsky S-57, a planned experimental American aircraft Siemens S57, a Siemens mobile phone