Fundamental law(s) may refer to:

• Organic law, in particular,
  • Constitution, in particular,
    • The Russian Constitution of 1906
    • The German Grundgesetz (more commonly translated as "Basic Law")
    • The four individual laws that together make up the Constitution of Sweden
    • The Fundamental Laws of England
    • The Fundamental Law of Vatican City State
    • The Fundamental Law of Hungary
  • The Basic Laws of a country that does not use the term "constitution" or has an uncodified constitution
• Any of the fundamental physical laws of the universe
• In Abrahmic religions, The Ten Commandments