The Cabrillo Marine Aquarium was established in 1935, as a collection of samples of ocean life, a sort of small museum on the Cabrillo beach. In 1949, John Olguin, in charge of the lifeguards at Cabrillo Beach, was appointed museum manager. It became a popular aquarium by opening the place for spontaneous tours for groups and schools, and began evening curriculum of watching different mating habits of the different sea life.
In 1981 the museum moved to a new building, designed by Frank Gehry. The old building closed. During the 1990's the museum turned into an aquarium, mainly to emphasize its sea life collections. In 2004 a research center was added to the aquarium, and today there is an indoor and outdoor display area, an auditorium, labs, and offices.