Huygens (also Huijgens, Huigens, Huijgen/Huygen, or Huigen) is a Dutch patronymic surname, meaning "son of Hugo". Most references to "Huygens" are to the polymath Christiaan Huygens. Notable people with the surname include:

• Jan Huygen (1563–1611), Dutch voyager and historian
• Constantijn Huygens (1596–1687), Dutch poet, diplomat, scholar and composer
• Constantijn Huygens, Jr. (1628–1697), Dutch statesman, soldier, and telescope maker, son of Constantijn Huygens
• Christiaan Huygens (1629–1695), Dutch mathematician, physicist and astronomer, son of Constantijn Huygens
• Lodewijck Huygens (1631–1699), Dutch diplomat, the third son of Constantijn Huygens
• Cornélie Huygens (1848–1902), Dutch writer, social democrat and feminist
• Léon Huygens (1876–1918), Belgian painter
• Jan Huijgen (1888–1964), Dutch speedwalker
• Christiaan Huijgens (1897–1963), Dutch long-distance runner
• Wil Huygen (1922–2009), Dutch children's and fantasy writer, e.g. of Gnomes

Named after Constantijn Sr

• Constantijn Huygens Prize, Dutch literary award
• Huygens Institute for Dutch History

Named after Christiaan Huygens

Astronomy:

• Cassini–Huygens, mission to Saturn and Titan
  • Huygens (spacecraft), the probe of above mission which landed on Saturn's moon Titan in 2005
• 2801 Huygens, an asteroid
• Huygens (crater), a Martian crater
• Mons Huygens, a mountain of Earth's Moon
• Huygens Gap, main gap in the rings of Saturn

Physics:

• Huygens' principle regarding wave propagation
• Huygens law regarding pendulums
• Huygens–Steiner theorem regarding moment of inertia

Mathematics and games:

• Huygens' tritone, a musical interval
• Huygens lemniscate, a figure eight curve

Microscopes:

• Huygens eyepiece, first compound eye piece
• Huygens Software, a microscope image processing package