Kōzu-gū is a Shinto Shrine in Ōsaka, Japan. It honors Emperor Nintoku. He was the 16th emperor. He reigned from 313 to 399. Emperor Nintoku named the area Kōzu-gū. This area is now known as Ōsaka.

One day, Emperor Nintoku looked at the city and he didn't see much smoke from cooking in the city. This meant the people were poor. He removed all taxes to help them. This made him very popular.

In 866, Emperor Seiwa became interested in this place. He was the 56th emperor. He reigned from 858 to 876. He ordered a search for the old capital's ruins. A shrine was built on the site. This became the Kōzu-gū shrine.

During Emperor Ōgimachi's reign, changes happened. He reigned from 1577 to 1586. Toyotomi Hideyoshi was building Ōsaka Castle then. The shrine was in the castle area. In 1583, the shrine's shintai was moved. It went to Himekoso Jinja. This is Kōzu-gū's current location.

In 1872, Kōzu-gū became a Prefectural Shrine. In 1921, the Osaka City Anthem [ja] was made. It mentions Emperor Nintoku. It talks about the city's prosperity.

The shrine was almost destroyed in 1945. This was during US air raids. It was rebuilt by 1961.

Kōzu-gū is important for rakugo. Rakugo is a Japanese art form. Many rakugo shows have been held here. Katsura Bunshi VI, a famous artist, performed here in 2015.

The shrine has several deities. The main deity is Emperor Nintoku. There are subordinate shrines. These include Himekoso Jinja, Takakura Inari, and Yaui Inari Jinja. Tani Massha has more shrines. These are Shiragiku Jinja, Shinnen Jinja, and Jōkō Jinja.

It holds a cherry blossom festival on April 7.

34°40′08″N 135°30′50″E / 34.6689°N 135.5139°E / 34.6689; 135.5139