The Clandeboye Estate, near Bangor, is home to Clandeboye Yoghurt.
It will build a new factory there and create 13 new jobs, with the aim of increasing production and growing sales internationally.
General manager Bryan Boggs said: “This will give us the capacity to produce up to 80 tonnes of yoghurt per week, over four times what we normally produce.
“All of this combined will help us to increase our export sales and expand in the Great Britain market.”
Over the last 12 years, Clandeboye Estate has built its farm-based artisan yoghurt brand into a premium offering.
Invest NI’s support has helped it to grow in Ireland and Britain, with major retailers such as Aldi, Sainsbury’s, Tesco and Asda stocking its products.
Invest NI has offered the company £470,000 support towards the new factory and machinery.
The project is part-financed by the European Regional Development Fund under the Investment for Growth and Jobs Programme 2014-2020.