Masaki Aiba is a Japanese idol, singer, actor, television personality and radio host. He is a member of the Japanese boy band Arashi.
Aiba began his career in the entertainment industry when he joined the Japanese talent agency Johnny & Associates in 1996 at the age of 13. Prior to his debut as a singer with Arashi in 1999, Aiba started an acting career when he was cast as the lead role of Gordie for the stage play Stand by Me, which was based on the film of the same name. About five years after his debut as a singer with Arashi in 1999, he became one of the co-hosts of the variety show Tensai Shimura Dōbutsuen (天才！志村どうぶつ園, Genius! Shimura Zoo?) in 2004, making him the first member of Arashi to regularly participate in a variety show not primarily hosted by Arashi.
Aiba was born in Chiba as the first child of his family. He has a younger brother who is four years younger. Aiba was raised by his grandparents until he was four years old because his parents were busy running their newly-opened Chinese cuisine restaurant then.
Prior to joining Johnny & Associates, Aiba watched a program called I Love SMAP and saw SMAP playing basketball on television. Wanting to play basketball with them, he sent in the application to join the talent agency himself, without exactly knowing what the agency specialized in until the day of auditions.
Aiba became a Johnny's Jr. in August 1996 at the age of 13