Yukio ("Koyuki") Tanaka
The main character, the series follows his rapid development from an average person to an outstanding guitarist. Being extremely polite, he cannot help but let others push him around, a possible metaphoric stereotype on the very proper and manner conscious Japanese society. Recruited as the last member of BECK, he serves as the second guitarist and vocalist, and has a very beautiful voice that is mostly used for Beck's slower songs. He owns a Fender Telecaster.
Ryusuke ("Ray") Minami
A Japanese character with a long history in America, he speaks fluent English, and frequently uses both Japanese and English in his conversations. He lives alone in a shack by the fishing pond. His skills and taste in music inspire Koyuki to take up the guitar. The band's creator, Ryusuke is BECK's lead guitarist.
Maho Minami
Ryusuke's sister and a talented singer with a strange relationship with Koyuki. At times she seems attracted to him, others she brushes him off with little regard to his often ignored feelings.
Yoshiyuki Taira
The first recruited member of BECK, Taira is the bassist, and the most talented band member next to Ryusuke. He plays Music Man StingRay bass. Little is known about him, and his attitude may sometimes come off as uncaring. He has been seen working as a traffic officer.
Tsunemi Chiba
Main vocalist for BECK, he is the key member that Ryusuke needed to bring Taira into the band. Compared to Koyuki, his voice is more punk and rock oriented, like the majority of the band's songs. He also named the band "Beck" after staring at Ryusuke's dog for a few moments.
Yuji ("Saku") Sakurai
The fourth member to join, he was also Koyuki's first good friend, sticking with him even when the school bully and his gang beat him up for breaking the silent treatment on Koyuki. He is the drummer, inspired by his brother, and replaces the original drummer of BECK who followed Ryusuke from his original band, Serial Mama.