Twenty-year-old full-back Bellerin enjoyed a breakthrough season with the Gunners in the last campaign, making the most of the opportunity presented to him by Mathieu Debuchy's injury.
He made 28 appearances and scored twice after proving his worth on the right side of Arsenal's defence.
Arsenal signed Bellerin from Barcelona in the summer of 2011 and he was promoted to the first team a year ago.
A short statement from Arsenal read: "Everyone at the club looks forward to Hector's continued progress with the club."
Source : PA