She has been promoted from vice-captain, a role which will now be filled by wicketkeeper-batsman and fellow England international, Sarah Taylor.
Holly said of her new role: “I am absolutely thrilled to be named Sussex captain. Having grown up playing cricket for Sussex it is such an honour to have been given this accolade.
“I am thoroughly looking forward to leading such a talented group of players to what hopefully will be just as successful a season as last year.”
Holly has represented the Sussex Women’s side since 2005 as well as making her England debut in the same year at the age of just 15.
Sussex Women’s Coach Charlotte Burton, said: “Both players have a wealth of experience and knowledge of the game. They are highly respected by all the team and I know they will get the most out of all the players this season.
“I am looking forward to working with Holly and Sarah in their new roles and our goal is to win both the County Championship and the T20.”