Sue Peters, the current chief executive, is to become the organisation's managing director of investments. A spokesman for the fund said the move was a promotion.
The fund has begun its search for a new chief executive, a role that commands a salary of £100,000.
It has published a series of adverts, the first of which appeared in the Financial Times last week. The advert read: "Working with the dynamic new chair, Stephen Bubb, there's Whitehall funding to secure, growth plans to drive, a strategic vision to define and a profile to raise."
The fund's board is also due to be reorganised. It plans to recruit at least two more trustees with financial expertise, and one of the existing trustees, private equity specialist Simon Davidson, has been appointed deputy chair.
The headhunting firm hired to find a new chief executive is Rockpools, which is also recruitment partner to Acevo, the chief executives body run by Bubb.
Both Peters and Bubb were on holiday and unavailable for comment.