Yum!, the owner of the Pizza Hut brand, has sold its dine-in business to investment firm Rutland Partners.
The restructuring specialists said they would invest £20m as part of a wider plan to refurbish the 330 restaurants.
Pizza Hut will continue to be operated as a franchise by Yum!, which also owns KFC and Taco Bell.
The US-based company said that following the sale it would focus on growing its Pizza Hut delivery business in the UK.
Nick Morrill, managing partner of Rutland, said the "iconic appeal" of Pizza Hut, which opened its first branch in 1973 and is known for its variety of pizzas and free salad bar, was exciting.
"The business has had its fair share of challenges over the past few years but the management team has put a clear turnaround plan in place that has already led to much improved performance over the past 12 months," he said.
"We are excited by the prospect of working with the management to drive the turnaround to completion."
And Jens Hofma, managing director of the Pizza Hut dine-in business, said the investment would help his team "inject fun, energy and quality back into our restaurants".
The news comes after fast-food rival McDonalds saw a rare fall in sales amid the global economic downturn.
The world's largest burger chain is expected to increase promotions after reporting its first monthly restaurant sales decline in nine years, as it lost customers to competitors including Burger King (NYSE: BKC - news) .