The aquarium is accredited as a Museum-equivalent facilities by the Museum Act from Ministry of Education, Culture, Sports, Science and Technology.

The prefectural Oarai aquarium was built several hundred meters south of the current building, and has a gate with a Ryugu castle motif and a basin-like appearance.

By the time it closed in September 1970 to increase the floor space, a total of 2.6 million people visited.

[4] In particular, aquariums focusing on breeding the symbol mark "shark", and the number of species is 59 (as of April 2021), which is the largest in Japan.

There is a taxidermied basking shark (total length 8.3 m (27 ft)) and the largest kids' corner in Japanese aquariums.

It is an area where ocean sunfish and sharks are captivity, and aquarium are focusing on the exhibition and education of the Coral and Okhotsk Seas.

Hands-on exhibits in these areas let visitors learn about the anatomy and behavior of fish and other sea life.

The exhibit contains sections on seaweed, plankton, and sharks, as well as a display where visitors can hear the calls of all 18 penguin species.