Ōyama-tsumi or Ohoyama-tsumi (Kojiki: 大山津見神 or Nihon Shoki: 大山祇神, 大山積神, 大山罪神), also Ōyama-tsumi-mi'oya-no-mikoto (大山祇御祖命), is a god of mountains, sea, and war in Japanese mythology.

After which he gave birth with Kaya-no-hime (鹿屋野比売神), also known as No-zuchi (野椎神), female deity from their union, the following gods pairs of eight were born:[citation needed] Other children of Ōyama-tsumi who are parentless without a mother: including the twin deities: However, in the Nihon Shoki, Ōyama-tsumi is supposed to be born when Izanagi slashed his child, Kagutsuchi (軻遇突智).

[citation needed] Afterwards, the lineage falls together with his descendants of his half-brother Susanoo, with the union of Ōyama-tsumi first daughter, Kamu'ō-ichi-hime (神大市比売), between them gave birth to Ōtoshi (or Toshigami) and Uka-no-mitama.

Then Yashimajinumi married Ōyama-tsumi's daughter Konohachiru-hime (木花知流比売), from their union gave birth to the male deity Fuwanomojikunusunu/ Fuwanomodjikunusunu (布波能母遅久奴須奴神, or Fuhanomojikunusunu/ Fuhanomodjikunusunu).

[citation needed] In the myth of Tenson Kōrin (天孫降臨), the descent of Amaterasu's grandson Ninigi-no-Mikoto from Heaven (Takamagahara) to Ashihara no Nakatsukuni, Ninigi has encountered Ōyama-tsumi's daughter Ko-no-hanasakuya-hime (木花之佐久夜毘売),[1] - the kami of Mount Fuji, Ōyama-tsumi has offered both Ko-no-hanasakuya-hime and her older sister Iwanaga-hime (石長比売).