Already 10 companies - including telecoms group AT&T, Ford, Procter & Gamble and Universal Pictures have signed up to advertise during the trials.
Some will sponsor the programmes while others have created adverts specifically to be used during the show.
New formats
"It's really an opportunity for us to learn about a different model," said Disney-ABC TV group president Anne Sweeney.
"It's more importantly recognising that none of us can live in a world of just one business model."
As media audiences increasingly fragment, broadcasters and other media outlets have found it increasingly difficult to boost advertising revenues.
ABC already offers advert-free downloads of its TV shows for iPod users - but at a price of $1.99 per episode.
"Going direct over a broadband connection is a very smart business and I think you'll see other broadcasters follow suit," Pali Research analyst Rich Greenfield told Reuters.
"This just continues to bolster our view that you should be investing in content and programming over pure distribution" like cable operators, he added.
But experts warned that the move could spell problems for local television stations and cable operators who could find it even harder to drum up advertisers.
Internet expansion
Disney-ABC plan to begin the two-month pilot - which will involve the shows Desperate Housewives, Lost, Commander In Chief and Alias - in May on ABC's website ABC.com.
The episodes will only be available to internet users with broadband connections and US internet addresses to protect foreign broadcasting rights.
Meanwhile, Disney also said it planned to launch its own high-speed internet channel for soap fans.
Soapnetic will be available to subscribers to Verizon's internet services from 17 April.
The news pushed Disney's shares almost 1% higher to $27.79 in late afternoon trade.
