Hachikō, sometimes known in Japanese as 忠犬ハチ公 (chūken hachikō, lit. 'faithful dog Hachiko'), was an Akita dog born in November, 1923, in the city of Odate, Akita Prefecture. In 1924, he was brought to Tokyo by his owner, Eisaburo Ueno, a professor in the agriculture department at the University of Tokyo. During his owner's life, Hachiko saw him off from the front door and greeted him at the end of the day at the nearby Shibuya Station. Even after Ueno's death in May, 1925, Hachiko returned every day to the station to wait for him, and did so for the next eleven years.

Hachiko's devotion to his lost master moved those around him, who nicknamed him "faithful dog," though some speculate that he kept returning because of the handouts he received from street vendors (upon his death, an autopsy revealed remnants of what were apparently yakitori skewers in his stomach). In April, 1934, a bronze statue in his likeness was erected at Shibuya Station, and Hachiko himself was present at its unveiling. The statue was recycled for the war effort during World War II, but another statue was erected in August, 1947, which still stands and is an extremely popular meeting spot. A similar statue stands in Hachiko's hometown, in front of Odate Station.

Hachiko died in March 1935 of filariasis. His stuffed and mounted remains are kept at the National Science Museum in Ueno, Tokyo.

Hachiko was the subject of the 1987 movie Hachiko Monogatari.