Lu or LU may stand for:

• Lu, the Chinese family names represented by the characters 呂(吕), 陸(陆), 路, 盧(卢), or 魯(鲁). A family by that name (呂) was a prominent supporter of the Eastern Jin Dynasty after the Han Zhao attacked the Jin.
• Lu (ethnic group) , an ethnic group in Vietnam
• Lu (music) , a Tibetan style of folk music
• LU factorization of matrix
• Lucerne, canton of Switzerland
• lutetium (Lu), symbol for the chemical element
• Luxembourg (ISO country code)
• London Underground, the metro system in London.
• 鲁, or Lǔ, an abbreviation for the Shandong province of the People's Republic of China
• Lu (路) is sometimes translated as Circuit.