The deal, announced today, will see Greene King take control of the chain of 36 seafood restaurants, which are primarily based in the south-east of England.
It has outlined plans to increase the number of sites by 20% by April 2008, with a medium-term view of doubling the estate - including converting a number of former Greene King pubs.
Rooney Anand, chief executive of Greene King, said: "Loch Fyne is a high-quality, well-respected British restaurant brand which gives us greater access to the premium end of the market and brings to our business further operational expertise.
"We have a strong track record of maximising the benefits from our acquisitions and this will be no exception: we greatly look forward to welcoming our new colleagues on board."
Mark Derry, chief executive of Loch Fyne Restaurants, said: "The tie-up with Greene King is an excellent development for Loch Fyne. It gives us the opportunity to capitalise on our already strong reputation and to accelerate the expansion of our business."
Projected figures show that by June 2008 Loch Fyne should post a pre-tax profit of £10m (£8m if overheads are included). The acquisition is funded by existing debt facilities at Greene King with profits going directly to the bottom line.
By Christopher Walton