Know your enemy (or know thine enemy) is a saying derived from Sun Tzu's The Art of War.

It may also refer to:

• Know Your Enemy (Lȧȧz Rockit album), 1987
• Know Your Enemy (Manic Street Preachers album), 2001
• Know Your Enemy, an album by Behind Enemy Lines
• "Know Your Enemy" (Green Day song), 2009
• "Know Your Enemy" (Rage Against the Machine song), 1992
• "Know Your Enemy", a song by Hybrid from the album Morning Sci-Fi
• "Know Your Enemy", a song composed by Yoko Kanno from Ghost in the Shell: Stand Alone Complex O.S.T. 3
• "Know Your Enemy", a song by Killswitch Engage from Atonement

• Know Your Enemy (podcast), American political podcast
• Know Your Enemy: Japan, a 1945 American propaganda film
• "Know Your Enemy", a 2018 episode of Voltron: Legendary Defender

• "Know Thy Enemy", an episode of the television series The Vampire Diaries