Laozi (also Lao-Tzu or Lao-Tze) was a philosopher and poet of ancient China. He is known as the reputed author of the Tao Te Ching and the founder of philosophical Taoism, and as a deity in religious Taoism and traditional Chinese religions.

Although a legendary figure, he is usually dated to around the 6th century BCE and reckoned a contemporary of Confucius, but some historians contend that he actually lived during the period of the 5th or 4th century BCE.

A central figure in Chinese culture, Laozi is claimed by both the emperors of the Tang dynasty and modern people of the Li surname as a founder of their lineage. Throughout history, Laozi's work has been embraced by various anti-authoritarian movements.