One Piece (stylized as ONE PIECE) is a Japanese manga series written and illustrated by Eiichiro Oda. It has been serialized in Shueisha's Weekly Shonen Jump magazine since July 1997, with its individual chapters compiled into 96 tankobon volumes as of April 2020.

One Piece has received praise for its storytelling, art, characterization, and humor. Several volumes of the manga have broken publishing records, including the highest initial print run of any book in Japan. The official website for Eiichiro Oda's One Piece manga announced that the manga has set the Guinness World Record for 'the most copies published for the same comic book series by a single author'. As of April 2020, the manga had over 470 million copies in circulation in 43 countries worldwide, making it the best-selling manga series in history. It became the best-selling manga for the eleventh consecutive year in 2018. One Piece is one of the highest-grossing media franchises of all time, estimated to have generated more than $21 billion in total franchise revenue, from the manga, anime, films, games and merchandise.