A Chinese character, also known as a Han character (汉字 / 漢字; Hànzì), is a logogram used in writing Chinese (hanzi), Japanese (kanji), less frequently Korean (hanja), and formerly Vietnamese (hán tự), and other languages. Chinese characters are also known as sinographs, and the Chinese writing system as sinography. Chinese characters represent the oldest continuously used system of writing in the world.

The number of Chinese characters contained in the Kangxi dictionary is approximately 47,035, although a large number of these are rarely used variants accumulated throughout history. Studies carried out in China have shown that literacy in the Chinese language requires a knowledge of only between three and four thousand characters.

In the Chinese writing system, the characters are mono-syllabic, each usually corresponding to a spoken syllable with a basic meaning. However, although Chinese words may be formed by characters with basic meanings, a majority of words in Mandarin Chinese require two or more characters to write (thus are poly-syllabic) but have meaning that is distinct from but dependent on the characters they are made from. Cognates in the various Chinese languages/dialects which have the same or similar meaning but different pronunciations can be written with the same character.

Chinese characters have also been used and in some cases continue to be used in other languages, most significantly Japanese (where a single character can represent several spoken syllables), Korean, and Vietnamese. Chinese characters are used both by meaning to represent native words, ignoring the Chinese pronunciation, and by meaning and sound, to represent Chinese loanwords. These foreign pronunciations of Chinese characters are known as Sinoxenic pronunciations, and have been useful in the reconstruction of Ancient Chinese.