EU membership helps UK businesses trade on a level playing field, bosses have told Catherine Bearder MEP.
The University of Kent's Innovation Centre has helped kick-start a string of companies in the county.
Catherine visited the centre on Tuesday (July 16) to find out how the region is creating work and encouraging new businesses.
She said: "The EU promotes growth and jobs in the UK and business leaders are telling me life would be tougher outside.
"The University of Kent is a great example of a success story, which is great for the county, and great for local jobs."
MPJ Design is one of the start-up companies based at the Innovation Centre.
Company owner Martin Jewiss said: "Being in Europe is really important.
"I am sure we could adapt if we left, but it could potentially give our competitors on the continent an advantage if we could not trade on a level playing field."
The Kent Enterprise Hub, also based at the university, has helped 58 businesses develop since 2010.
Steven Trim set up a company there producing pharmaceuticals from animal venom. He also said being based in Europe was important for his company.
He added: "Clients like to buy from us because they know that Europe has a very high standard of health and safety and so they will be able to trust our products."
The University of Kent is one of the county's biggest employers and generates £600m for the South East economy every year.
It is proud to call itself the UK's European University and has sites in Brussels and Paris.