Power of Three may refer to:

• Power of three, a number of the form 3ⁿ
• Third power, a number of the form n³
• Power of Three (novel), a novel by Diana Wynne Jones
• Power of Three (Fatso Jetson album)
• Power of Three (Michel Petrucciani album)
• Power of Three (Charmed)
• "The Power of Three" (Doctor Who)
• "The Power of Three", an episode of Teenage Mutant Ninja Turtles
• "The Power of Three", a 2013 episode of Ancient Aliens
• Warriors: Power of Three, an arc in the fantasy novel series Warriors by Erin Hunter
• The Power of Three, a music album by Monte Pittman