Li, li, or LI may refer to:

• Li (surname), including:
  • Li (surname 李), one of the most common surnames in the world
  • Li (surname 黎), the 84th most common surname in China
  • Li (surname 栗), the 249th most common surname in China
  • Li (surname 利), the 299th most common surname in China
  • Li (surname 厉), a Chinese surname
  • Li (surname 郦), a Chinese surname
  • Li (surname 理), a rare Chinese surname
  • Li (surname 莉), a rare surname of the Hui people

.li is the Internet country code top-level domain (ccTLD) for Liechtenstein. The .li TLD was created in 1993. The domain is sponsored and administered by the University of Liechtenstein in Vaduz. Registration of .li domain names used to be managed by SWITCH, administrator of Switzerland's .ch ccTLD. In February 2013, SWITCH discontinued its .li registration service for private customers, delegating it to a number of recognized partner firms.

Li is a classical Chinese word which is commonly used in Chinese philosophy, particularly within Confucianism. Li does not encompass a definitive object but rather a somewhat abstract idea and, as such, is translated in a number of different ways. Wing-tsit Chan explains that li originally meant "a religious sacrifice but has come to mean ceremony, ritual, decorum, rules of propriety, good form, good custom, etc., and has even been equated with Natural Law."

Li is the pinyin and Wade–Giles romanization (spelled Lí, Lǐ, or Lì when pinyin tone diacritics are used) of several distinct Chinese surnames that are written with different characters in Chinese. Li 李 is by far the most common among them, shared by 93 million people in China, and more than 100 million worldwide. It is the second most common Chinese surname behind Wang.