Samuel Alapai Kahanamoku (November 4, 1902 – April 26, 1966) was an American competition swimmer who represented the United States at the 1924 Summer Olympics in Paris, where he won a bronze medal in the men's 100-meter freestyle event.

Like his elder brother Duke, who was 12 years older than Sam, he was a talented swimmer and surfer.

[2] Sam and Duke competed together at the 1924 Summer Olympics in the men's 100-meter freestyle event.

[5] In 1935, the Kahanamoku brothers hosted Doris Duke and her husband James Cromwell, who were visiting Hawaii on her honeymoon tour.

Sonia Vrooman Lien Kahanamoku (September 20, 1935 – March 9, 2016), their daughter, did not know her father's true identity until 2010.