Choi Si-won (born April 7, 1986, officially registered on February 10, 1987) is a South Korean singer-songwriter and actor. He is a member of the South Korean boy band Super Junior and its Mandopop subgroup, Super Junior-M. Choi is one of the first four South Korean artists to appear on Chinese postage stamps.
Aside from being a member of Super Junior, Siwon has also ventured into solo activities mainly in acting. He played the lead roles as Sung Min-Woo in the Korean drama Oh! My Lady (2010) and as Kim Sun-Woo in Poseidon (2011). Choi also played supporting roles in the dramas She Was Pretty, The King of Dramas, and Athena: Goddess of War. In 2015, he has participated in Chinese language films such as Helios, To the Fore, and in the historical action film Dragon Blade starring Jackie Chan.