Orion is the name of various ships and a ship class:
Naval
HSwMS Orion (A201), Royal Swedish Navy signals intelligence ship
HMAS Orion (S 61), Royal Australian Navy submarine
HMS Orion, various British Royal Navy ships
Orion-class battleship, British Royal Navy ship class
USS Orion, various U.S. Navy ships
BAE Orion (H-101), Ecuadorian Navy ship, originally USS Mulberry (AN-27)
German auxiliary cruiser Orion (HSK-1), Nazi Germany naval ship
French ship Orion (1787), Royal French Navy ship of the line
Civilian
SS Orion, Swedish salvage ship and museum ship
MV Orion (also: MS Orion, MY Orion) National Geographic exploration ship
MS Nordic Orion, Arctic ice-strengthened cargo ship
RMS Orion, Orient Steam Navigation modified Orama-class ocean liner
Orion (paddle steamer), a British ferry which sank in 1850
