Yoko Ono Lennon (/ˈoʊnoʊ/ OH-noh; Japanese: 小野 洋子, romanized: Ono Yōko, usually spelled in katakana オノ・ヨーコ; born February 18, 1933) is a Japanese multimedia artist, singer, songwriter and peace activist. Her work also encompasses performance art, which she performs in both English and Japanese, and filmmaking. She was married to English singer-songwriter John Lennon of the Beatles from 1969 until his murder in 1980.

Ono grew up in Tokyo and moved to New York in 1953 to live with her family. She became involved in New York City's downtown artists scene, which included the Fluxus group. With their performance Bed-Ins for Peace in Amsterdam and Montreal in 1969, Ono and Lennon used their honeymoon at the Hilton Amsterdam as a stage for public protests against the Vietnam War. The feminist themes of her music have influenced musicians as diverse as the B-52s and Meredith Monk. She achieved commercial and critical acclaim in 1980 with the chart-topping album Double Fantasy, a collaboration with Lennon that was released three weeks before his murder.