Ian Griffiths will step in to lead the executive team while the broadcaster seeks a replacement for Crozier. Griffiths has been given a new combined role of chief operating officer and group finance director.
Sir Peter Bazalgette, ITV’s chairman, will also become executive chairman on an interim basis.
ITV said it has "a well developed succession plan in place" and will announce Crozier’s successor "in due course".
Crozier departs on 30 June and will be "paid in line with his contract and in recognition of his tremendous contribution to the success of ITV".
He said he now wants to "build a portfolio of roles across the PLC and private sectors" having spent 21 years as a chief executive across four "very different" industries.
Bazalgette said that Crozier has been speaking to him and the board about his future plans "for some time now".
Bazalgette added: "Under Adam, external revenues have grown by over a billion pounds, non-NAR revenues have more than doubled to almost £1.9bn, EBITA has grown by 338% and adjusted earnings per share have grown by 844%.
"He has also built a very strong management team and a clear strategy that this team will remain focussed on delivering.
"Coupled with our robust balance sheet and strong underlying cash flows Adam has created a real legacy that will allow ITV to continue to invest and also deliver sustainable returns to shareholders."
Crozier said: "Going forward, our strategy remains the right one for ITV and I leave behind a strong and talented management team who I know will continue to execute it with energy and confidence."