Luke Wells has signed a new deal at Sussex to keep him at the County Ground until 2014.
The 20-year-old batsman, who hit a career-best 174 against Yorkshire in May, compiled 824 first-class runs this year, including three centuries.
Wells said: "It's exciting to know that I've got another three years at the club I've been raised at.
"I'm absolutely chuffed to have extended my contract and very grateful to the coaches for backing me."
He added: "I am keen to press on and become an integral part of the team in all formats."
Sussex's professional cricket manager Mark Robinson continued: "Luke impressed everyone this year, not only with the volume of runs he scored in the first half of the year, but his hunger and work rate and maturity at the crease.
"I am sure he will have an outstanding future in the game."