Fozzard, 36, was appointed last March, just days after bringing to an end his 19-year playing career with Leeds, Huddersfield, Warrington, St Helens, Hull KR, Casteford, Dewsbury and Great Britain after failing to recover from a shoulder injury.
"It is with regret that today I have resigned from the Castleford Tigers Rugby League Football Club," he said on his Twitter account.
Castleford have yet to comment on the announcement.
Just a week ago, Ferres resigned from his post seven months after taking over from Richard Wright, citing differences with the club's directors, and head of youth development Steve Gill was appointed to the role on a temporary basis.
- Sports & Recreation