Torii is a traditional Japanese gate most commonly found at the entrance of or within a Shinto shrine, where it symbolically marks the transition from the mundane to the sacred.

The presence of a torii at the entrance is usually the simplest way to identify Shinto shrines, and a small torii icon represents them on Japanese road maps.

The first appearance of torii gates in Japan can be reliably pinpointed to at least the mid-Heian period; they are mentioned in a text written in 922. The oldest existing stone torii was built in the 12th century and belongs to a Hachiman Shrine in Yamagata prefecture. The oldest existing wooden torii is a ryōbu torii (see description below) at Kubō Hachiman Shrine in Yamanashi prefecture built in 1535.

Torii gates were traditionally made from wood or stone, but today they can be also made of reinforced concrete, copper, stainless steel or other materials. They are usually either unpainted or painted vermilion with a black upper lintel. Inari shrines typically have many torii because those who have been successful in business often donate in gratitude a torii to Inari, kami of fertility and industry. Fushimi Inari-taisha in Kyoto has thousands of such torii, each bearing the donor's name.