Saint Seiya: Soul of Gold (聖闘士星矢（セイントセイヤ） 黄金魂（ソウル オブ ゴールド）, Seinto Seiya: Souru obu Gōrudo) is a Japanese ONA anime series, a spin-off from the classic anime Saint Seiya, the animated adaptation of Masami Kurumada's manga of the same name.The series was announced on October 29 at the 2014 Tamashii Nation Figure Expo in Japan, revealing it would focus on the deceased Gold Saints in the aftermath of Athena's battle against Hades in the 20th century.

It was also revealed that the series approach would be an original anime story, as it would not be an adaptation of any of the arcs contained in Kurumada's manga or other related spinoffs in the franchise.

An official event was to be held on October 31, 2014, at the Tamashii Nation 2014 Expo in Japan, to further introduce the series to the specialized media and to the public. Saint Seiya: Soul of Gold was released on April 11, 2015. Soul of Gold is part of the projects that commemorate the 40th anniversary of Kurumada as a manga artist. Soul of Gold drew a 50 million viewership worldwide by September 2015.