The Hull-based firm has snapped up Crown Chicken as it ramps up plans to expand its reach outside the pork business.
Crown - and its subsidiary Crown Chicken Limited - breeds, rears and processes fresh chicken for grocers and manufacturers across the UK.
Cranswick's decision to bolster its poultry business comes after it bought premium cooked chicken producer Benson Park in October 2014, with shares rising 4.8% as investors welcomed the deal.
Chief executive Adam Couch said the move marked an excellent opportunity for the firm to develop its UK poultry business.
He added: "This acquisition represents important progress in our long-term growth strategy of developing new product channels in both pork and other proteins."
Crown, which employs about 400 people at sites in Norfolk and Suffolk, recorded revenues of £83.8 million to December 31 last year.
The company also owns a milling operation, creating animal feed for pig and poultry firms across East Anglia.
The deal will see Crown's chairman David Thacker retire from the business, while mill director Nigel Armes and agricultural director Matthew Ward will stay on at the firm.