LLL may refer to:

Businesses and organisations

  • L3 Technologies, an American defense contractor formerly with the NYSE stock symbol LLL
  • La Leche League, an organization that promotes breastfeeding

Education

  • LL.L (Legum Licentiatus), a degree in civil law at various Canadian universities (especially in Québec)
  • Lifelong learning
  • Lambda Lambda Lambda, a co-ed fraternity

Entertainment

  • Leisure Suit Larry in the Land of the Lounge Lizards, the first of a series of video games
  • Love's Labour's Lost, a comedy by William Shakespeare
  • Landau, Luckman, and Lake, a fictional holding company in Marvel Comics
  • LLL, the production code for the 1972 Doctor Who serial The Sea Devils
  • "L. L. L.", a 2015 song by Myth & Roid

Military units

  • Loyal Lusitanian Legion, a foreign volunteer corps of the British Army, that fought in the Peninsular War

Religion

  • Lutheran Laymen's League, also known as Lutheran Hour Ministries, a Christian outreach ministry
  • "Lunatic, Liar, or Lord", a common summary of Lewis's trilemma, a theological argument from C. S. Lewis

Science, technology, computing

  • Low-level programming language, such as machine code or assembly
  • Lenstra–Lenstra–Lovász lattice basis reduction algorithm, a polynomial time lattice reduction algorithm
  • Lowest Landau level, wave functions in quantum mechanics
  • Lovász local lemma, a lemma in probability theory
  • Lawrence Livermore Laboratory, now known as Lawrence Livermore National Laboratory, a scientific research laboratory in the United States
  • One of the programming languages used in Ethereum