The use of the fish as a symbol has its origin in very ancient folklore. Fish belong among the oldest mystic animals on account of their ability to live and swim beneath the water. In China fish are emblematic of wealth or abundance, not only because of their extremely plentiful presence in Chinese waters, but also because the characters for fish and superfluity are both pronounced yü.. Because of its reproductive powers and its happy conduct in its own element, the fish is also a symbol of regeneration, as well as of harmony and connubial bliss. Fish are reputed to swim in pairs, so a pair of fish are emblematic of the joys of union, especially of a sexual nature. This emblem is included in the signs of the footprint of Buddha.

In Japan swimming fish in general express the feeling of being free from restraints, encountering no obstacles, "like a fish in water", as well as intellectual freedom in particular. Moreover, dried fish plays an important role in presenting a gift to someone. In early times in Japan important presents were always accompanied by pieces of dried fish. This was a reminder of the fact that in old times people depended upon the food supplied by the sea. If anyone went for a journey overland, a piece of dried fish was taken along, originally for food but afterwards as a talisman for good luck and health. If represented as dead, fish are a symbol of plenty of food, in which case the are often shown laid on leaves of the sasa , a kind of low-growing bamboo.