Apostolos Siskos

Apostolos Siskos (; born 24 June 2005) is a Greek swimmer. He represented Greece at the 2024 Summer Olympics.

Career On 7 February 2023, Siskos verbally committed to swim collegiately at Harvard for the 2024–25 season. He represented Greece at the 2024 Summer Olympics and finished in 14th place in the 200 metre backstroke with a time of 1:57.77.

On 6 July 2026, he was selected to represent Greece at the 2026 European Aquatics Championships. During the European Championships he won a silver medal in the 200 metre backstroke with a national record time of 1:53.81. He also won a bronze medal in the 200 metre butterfly with a national record time of 1:54.13. He then competed at the 2026 Mediterranean Games where he served as a flag bearer for Greece during the opening ceremony. He won a gold medal in the 200 metre backstroke with a time of 1:55.95.