Keiko (circa 1976 - December 12, 2003) was an orca which performed in the first of the three Free Willy movies.

Keiko was captured near Iceland in 1979 and sold to the Icelandic aquarium in Hafnarfjörður. Three years later, he was sold to Marineland in Ontario, where he first started performing for the public and developing skin lesions indicative of poor health. He was then sold to Reino Aventura, an amusement park in Mexico City, in 1985.

The publicity from his role in Free Willy led to an effort by Warner Brothers Studio and schoolchildren around the world to find him a better home. Donations from the studio and Craig McCaw led to the establishment of the Free Willy Keiko Foundation in February 1995. With donations from the foundation, the Oregon Coast Aquarium in Newport, Oregon spent over $7 million to construct facilities to return him to health with the hope of returning him to the wild. He was airlifted by UPS to his new home in January 1996, weighing 3500 kg (7720 pounds). During his years in Oregon, he gained over a ton in weight.

The plan to return him to the wild was a topic of much controversy. Some felt his years of domestication made such a return impossible. Nevertheless, the next step in the plan happened on September 9, 1998, when he was flown to Klettsvik Bay in Vestmannaeyjar in Iceland. His day-to-day care became the responsibility of the Ocean Futures Society . He underwent training designed to prepare him for his eventual release, including supervised swims in the open ocean.

Keiko was released in July 2002. He traveled about 1400 km (870 miles) to the coast of Norway over a period of several days. In September, he followed a fishing boat to Halsa in Norway where he allowed fans to play with him and crawl over his back. His handlers soon thereafter enticed him to nearby Taknes Bay, hoping to discourage his interaction with humans.

He died suddenly on December 12, 2003, of pneumonia. He was 27 years of age, very old for a captive whale, but young for a wild one. Following requests from fans of the whale and its films, the Oregon Coast Aquarium held a memorial service for him on Friday 20th February 2004. 700 people attended the service at which the aquarium's veterinary chaplain said "Keiko was not one of our kind, but nonetheless was still one of us."