Tok Pisin (English: , ; Tok Pisin [ˌtok piˈsin]), often referred to by English speakers as New Guinea Pidgin or simply Pidgin, is a creole language spoken throughout Papua New Guinea. It is an official language of Papua New Guinea and the most widely used language in the country. However, in parts of the southern provinces of Western, Gulf, Central, Oro, and Milne Bay, the use of Tok Pisin has a shorter history and is less universal, especially among older people.

Between five and six million people use Tok Pisin to some degree, although not all speak it fluently. Many now learn it as a first language, in particular the children of parents or grandparents who originally spoke different languages (for example, a mother from Madang and a father from Rabaul). Urban families in particular, and those of police and defence force members, often communicate among themselves in Tok Pisin, either never gaining fluency in a local language (tok ples) or learning a local language as a second (or third) language, after Tok Pisin (and possibly English). Over the decades, Tok Pisin has increasingly overtaken Hiri Motu as the dominant lingua franca among town-dwellers. Perhaps one million people now use Tok Pisin as a primary language. Tok Pisin is slowly "crowding out" other languages of Papua New Guinea.