Khat or qat (Amharic: ጫት ch’at; Oromo: Jimaa, Somali: qaad, khaad, khat or chat, Arabic: القات al-qāt) is a flowering plant native to eastern and southern Africa. Khat contains the alkaloid cathinone, a stimulant, which is said to cause excitement, loss of appetite, and euphoria. Among communities from the areas where the plant is native, khat chewing has a history as a social custom dating back thousands of years analogous to the use of coca leaves in South America and betel nut in Asia.

The World Health Organization (WHO) classified it in 1980 as a drug of abuse that can produce psychological dependence, although the WHO does not consider khat addiction to be a serious problem.

The legality of khat varies by region. In many countries, khat might not be a specifically controlled substance but may nevertheless be illegal under more general laws. It is a specifically controlled substance in some countries including Canada, Germany, the United Kingdom, and the United States. By contrast, the production, sale, and consumption are legal in the nations where its use is traditional of those cultures, including Djibouti, Kenya, Uganda, Ethiopia, Somalia, Sudan and Yemen. In Israel, which hosts a population of Yemenite Jews, only the consumption of the plant's leaves in its natural state is permitted.