It has been celebrated unofficially since its original proposal in 1992 by Canada's International Centre for Ocean Development (ICOD) and the Ocean Institute of Canada (OIC) at the Earth Summit – UN Conference on Environment and Development (UNCED) in Rio de Janeiro, Brazil.
Mitteametlikult hakati ookeanide päeva tähistama juba 1992. aastal, mil selleks tegid ettepaneku Kanada rahvusvaheline ookeanide arenduskeskus (International Centre for Ocean Development, ICOD) ja Kanada Ookeaniinstituut (Ocean Institute of Canada, OIC) Earth Summitil – ÜRO keskkonna- ja arengukonverentsil (Conference on Environment and Development, UNCED) Rio de Janeiros Brasiilias.