CKY3 may refer to:

• The third of the CKY videos (Camp Kill Yourself), a series of videos by Bam Margera
• Norway House Water Aerodrome, the ICAO airport code for the airport in Canada

• HMS Hector (1774)
• HMS Hector (1861)
• HMS Helga
• HMS Helsingborg
• HMS Helverson
• HMS Hercule (1798)
• Hms hercules
• HMS Hercules (1759)
• HMS Hercules (1868)
• HMS Hermes (1913)
• HMS Hermione (1893)
• HMS Hermione (74)
• HMS Hero (1759)
• HMS Hero (1803)
• HMS Hero (1885)
• HMS Heron
• HMS Heureux
• HMS Heureux (1800)
• HMS Highflyer (1851)
• HMS Hildersham (M2705)
• HMS Hindostan
• HMS Hindostan (1841)
• HMS Hindustan
• HMS Hindustan (1903)
• HMS Hispaniola