Westlife manager Louis, who was the twins' mentor on The X Factor before they were voted off, will run their careers alongside the CEO of broadcasting company Global Group, Ashley Tabor.
They are looking into record deals and TV possibilities.
The pair were given the boot from the competition last month after their less-than-convincing vocal abilities became a cause celebre.
But despite often failing to impress Simon Cowell, the duo proved a hit with the public whose votes temporarily postponed their exit.
Louis said of the signing: "Despite all the doubters John and Edward proved themselves on The X Factor and I've always been convinced that they have a great career ahead of them.
"I'm delighted that I'll be able to continue to work with the pair. We're looking into music as well as TV deals but at this stage it is too early to give any exact details."
Tabor said: "Jedward are this year's X Factor phenomenon and I'm thrilled to be able to put the scale of the Global Group behind them alongside Louis, developing what I am sure will be a great career for them both. It's an exciting future."
Louis has come to an "amicable agreement" with Modest Management which had been contracted to represent the final 12 X Factor contestants, allowing them to join his team.
Modest will continue to represent the other finalists, who also handle previous winners Leona Lewis and Alexandra Burke.