Orion is the name of various ships and a ship class:

Naval

• BAE Orion, Ecuadorian Navy ship, originally USS Mulberry
• French ship Orion, Royal French Navy ship of the line
• German auxiliary cruiser Orion, a Nazi German auxiliary cruiser
• HMAS Orion, Royal Australian Navy submarine
• HMS Orion, various British Royal Navy ships
• Orion-class battleship, British Royal Navy battleship class
• HSwMS Orion, Royal Swedish Navy signals intelligence ship
• USS Orion, various US Navy ships

Civilian

• MS Nordic Orion, an Arctic ice-strengthened cargo ship
• MV Orion (also known as MS Orion, MY Orion), a National Geographic exploration ship
• MV Orion, a Greek ro-ro freight ferry, previously Pentland Ferries' Orcadia and Caledonian MacBrayne's Saturn
• Orion, a heavy lift vessel (HLV) operated by DEME Offshore, a subsidiary of the DEME Group.^[1]
• Orion (paddle steamer), a British ferry which sank in 1850
• RMS Orion, an Orient Steam Navigation modified Orama-class ocean liner
• SS Orion, a Swedish salvage ship and museum ship
• SS Prinz Oskar, renamed Orion by 1919