The nominees, which were selected by an independent committee, will be formally appointed to run a new organisation called the Green Purposes Company Ltd (GPC).
GPC, which will control a special share in the GIB once it is privatised, is designed to prevent large changes that could damage the bank's green remit, though the trustees will not have any other voting rights.
Most of the nominees are well known to the environment sector.
James Curran is an environmental scientist, former chief executive of the Scottish Environment Protection Agency (SEPA) and a non-executive member of the Scottish government's Climate Change Delivery Board.
Peter Young is founding director and former chair of the Aldersgate Group, an influential green business lobby.
They will work alongside Lord Teverson, chair of the Lords' EU select committee on energy and environment.
The two remaining trustees are Trevor Hutchings, director of advocacy at WWF, previously a senior civil servant at the now-defunct UK energy department, and experienced green infrastructure investor Tushita Ranchan.
Ranchan is the former managing director of a subsidiary of renewable energy group Masdar and a board member of London Array offshore wind farm.
Windpower Monthly's sister publication, ENDS, understands that Australian investment group Macquarie is now the preferred bidder for GIB, subject to ongoing due diligence checks by the group and the government.
An official announcement has yet to be made, but the government wants to complete the sale by the end of the financial year (March 2017).
The official price has yet to be disclosed, but as of October GIB had net capital commitments of £2 billion (€2.2 billion).
The GIB has supported nine offshore wind farms to-date.