Nick Daubney announced the news to fellow Conservative councillors after nine years in the leadership position.
While he will continue to remain a councillor in his ward of South Wootton in King's Lynn, Mr Daubney said it 'just felt right' to step down in plenty of time for a new leader to be elected.
He said: 'I've now made it clear to my fellow councillors that I will be stepping down as leader.
'It has been a difficult decision, but I do see this as a very positive move. I was keen to lead the party during the last election and we achieved amazing results.'
He added: 'The council is facing a huge amount of changes; particularly with the forthcoming devolution and changes to council funding - and I felt it best to hand that responsibility over to someone else.'
Mr Daubney has been a councillor in West Norfolk for 13 years, for four years he served as deputy leader.
Throughout his years as leader, he has focused improving the local economy of west Norfolk by branding it an attractive area for business and to visit.
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