Gent, who has been at the head of Vodafone since 1997, expressed his desire to retire to Vodafone chairman Lord MacLaurin earlier this year. Arun Sarin, the chief executive officer of Accel-KKR Telecom and a non-executive director of Vodafone, will replace him.
Arun joined Vodafone in 1999 after the group bought AirTouch Communications, where Arun was president and chief operating officer.
Upon the merger, Sarin became chief executive of the Americas and Asia region of Vodafone until 2000, when Vodafone's US mobile businesses were merged with others to form Verizon Wireless, of which Vodafone owns 45%.
Sarin, who reportedly earned £21m from the AirTouch takeover, is expected to intensify Vodafone's drive into third-generation data services and wireless internet.