The Competition and Markets Authority (CMA) said the new combination would not affect prices or quality of "hot pies, cold pies, sausage rolls, pasties and slices" in the Â£1bn sized market.
The two own brands such as Pork Farms, Millers, Walls and Bowyers.
As well as branded goods, they supply own label products to supermarkets.
Pork Farms already makes Kerry's Walls and Millers brands under licence.
The deal was first proposed in August last year.
Chris Peters, group managing director at Pork Farms Group, said: "The CMA's decision marks the start of an incredibly exciting new time for our business and our employees."
He said the deal would allow it to expand the product range.
He also said it would mean changes to the way it operated: "Our priority is to move ahead to integrate the Spalding and Poole businesses into the Pork Farms Group.
"We will now take stock of our entire business, taking into account our employees', customers', owners' and suppliers' needs... in what is an exciting and pivotal time in the UK chilled food market."
One of the biggest names in savoury pastries, Pork Farms Group, will be allowed to take over the pastries business of Kerry Foods.