Futarasan jinja (二荒山神社) is a Shinto shrine in the city of Nikkō, Tochigi Prefecture, Japan.

It is also known as Nikkō Futarasan Shrine, to distinguish it from the Utsunomiya Futarayama Jinja, which shares the same kanji in its name.

Many visitors go to all three, as well as to Rinnō-ji, which are part of the Shrines and Temples of Nikkō UNESCO World Heritage Site.

Archaeologists have found relics and ritual instruments from the Nara period confirming the site's age, and many of these artifacts have been designated national Important Cultural Properties.

The shrine was founded in 767 by Shōdō Shōnin (勝道上人), a Kegon school Buddhist priest who sought a training ground in the northern mountainous area of Shimotsuke Province.

The area had been sacred since at least the Yayoi period as Mount Nantai (also called Futarasan (二荒山)) was a sacred mountain worshipped as a go-shintai (御神体) (a yorishiro housing the enshrined kami), as it supplied streams of water, and therefore life, to the plains below, where people lived.

[4] The mountain not only provides water to the rice paddies below, but has the shape of the phallic stone rods found in pre-agricultural Jōmon sites.

[5] The shrine suffered during the Sengoku period as many of its estates were seized by the Late Hōjō clan and later by Toyotomi Hideyoshi.

[6] The Sacred Bridge (神橋, shinkyō) crossing the Daiya River belongs to the Futarasan Shrine.

Shōdō prayed and a 10 foot tall god named Jinja-Daiou appeared with two snakes twisted around his right arm.

Jinja-Daiou released the blue and red snakes and they transformed themselves into a rainbow-like bridge covered with sedge, which Shōdō and his followers could use to cross the river.