Kamogawa Sea World is a large scale comprehensive marine leisure center/museum equivalent facility located between the Tojo coast and Japan National Route 128 in Kamogawa city, Chiba Prefecture, Japan. It is not affiliated with SeaWorld in any way and is operated by Granvista Hotels & Resorts Co., Ltd. It is a public aquarium and is also a member of the Japanese Association of Zoos and Aquariums (JAZA). In 2021, the park celebrated the 50th anniversary of its opening. The aquarium is accredited as a Museum-equivalent facilities by the Museum Act from Ministry of Education, Culture, Sports, Science and Technology.

In October 1970, Yasushi Tourism Corporation launched a business. The park focused on marine animal exhibitions such as dolphins and sea lions, with breeding and training programs for orcas. There are now performances by marine animals other than killer whales. There are three different zones: the Eco Aquaroam, Tropical Island, and Rocky world, which contains most of the sea creatures, with about 11,000 on display.

By the opening of Sea World, resort hotels such as "Kamogawa Grand Tower" and ryokan / recreation facilities were built in the Kamogawa area, which was a sightseeing area until then, south Boso was transformed into a resort for a whole year. In addition, the hotel "Kamogawa Sea World Hotel" managed directly inside Sea World premises, was founded in 1971.

Since Yasu Tourism was absorbed and merged into Mitsui Kohmura (former North Coast Tourism, now Gran Vista) in 1986, it became the main facility of the company. In 1987, a new establishment of the Ocean Stadium which can accommodate about 2,000 people exclusively for orca performance, Eco Equalome which renewed indoor aquarium panolium in December 1996, Rocky World and Seika Performance only for July 1998 "The Rocky Stadium (about 1,000 people)" has been established, July 2001 has expanded the exhibition facilities, the tropical island to display the fishes in the South Pacific and the sea turtle beach new construction.

As a countermeasure for COVID-19, the number of visitors was restricted from July 23 to August 30, 2020.

So far, aquarium has succeeded in breeding fish and sea turtles. During 2003, a total of nine killer whales, walruses, Caspian seals, steller sea lions (two), California sea lions (two), and bottlenose dolphins (two) were born. In addition, the ocean sunfish named Kukey, who started captivity in 1982, set a world record for captivity for 2,993 days, living for eight years. Kukey was 72 cm (2.36 ft) at the time of delivery, but was 187 cm (6.14 ft) in size at the time of death. About 1-3 California sea lions are born every two years. In the past, steller sea lions gave birth at the same pace as other sea lions, but it seems that there are no plans for a while because the male "Nosa" died in 2007.

The creatures that have received the Japanese Association of Zoos and Aquariums (JAZA) Breeding Award are as follows. Pictures of the plates and the award-winning creatures are on display in the Eco Equalome.

Since December 2015, Kamogawa Sea World houses three killer whales – "Lovey" (female, born January 11, 1998), "Lara" (female, born February 8, 2001), "Ran" (female, born February 25, 2006), "Luna" (Female, born on July 19, 2012). Lovey, Lara, and Ran are sisters, and Luna is Lovey's daughter. In addition, two surviving killer whales Earth, and Lynn) were bred at the Port of Nagoya Public Aquarium, while Stella and Ran were transferred to Kobe Suma Sea World from Port of Nagoya Public Aquarium and Kamogawa Sea World respectively on 29 March 2024 and on 24 April 2024.