Engine manufacturer Cummins, based in Daventry, and hi-tech helicopter equipment firm Enterprise Control Systems at Wappenham, near Towcester, were named as award winners in the list published on the Queen's birthday on Saturday, April 21.
Cummins
, which make high horsepower diesel and gas engines is no stranger to the award having won on five previous occasions in 1979, 1981, 1984, 1995 and 2002.
The company has won the International Trade Award thanks to a significant increase in export sales over the last three years.
Overseas sales have more than doubled and more than 70 per cent of the firm's products are sold abroad.
It is the first time plant manager Peter Glover has accepted the award on behalf of the company which he joined in 2003.
He said: "With the competition getting tougher all the time, winning this year is even better than before. What is good about this award is that it recognises the contributions made by the whole workforce."
He said the plant, which has 854 employees, is the only site in the world to make exceptionally large diesel engines. The largest, at 91 litres, puts the average two-litre car engine into the shade with its 3,500 brake horsepower.
Mr Glover said: "The engines are used mainly in earth-moving equipment or as stand-by power generators.
"Our work is a continual process of improvement and we are continually looking to increase our capacity."
Enterprise Control Systems has received the Queen's Award for Innovation in recognition of the company's work in highly specialised encrypted digital video transmission systems.
The company, set up by Colin Bullock almost 20 years ago, employs 45 staff and supplies equipment used in the East Midlands Air Support helicopters, covering Northamptonshire, Warwickshire and Leicestershire, as well as those in the West Midlands and police forces across the country.
Mr Bullock, who is proud to head one of the few privately-owned British companies still involved in the defence industry, said: "As a local company, very much a part of the community, we are extremely proud to have received this award.
"It is a tribute to the commitment of our team.
"All our products are designed in-house. One of the key things for our clients is our ability to react quickly to their changing needs and develop equipment that best suits their requirements, rather than them having to deal with multi-nationals.
"We are experts in video downlinks for police and military helicopters, and the Queen's Award acknowledges our latest generation of encrypted digital equipment for air-to-ground video."