The actress, who plays Ashley Davenport in the ABC series, explained that the comparison was first made by her mother due to its melodramatic qualities.
"[It's] so soapy. My mum was like, 'It's Dallas's second coming'," she told Metro. "My mum loved that show. She loves Revenge too.
"None of us knew how popular it was going to be because there are no other soap dramas on, really."
Madekwe went on to speak of the backlash she has received from Revenge fans over her character's devious behaviour.
"You should see some of the things people tweet me," she said. "There have been death wishes on my Twitter timeline. I think its kind of nice people are that interested in it."
Madekwe married her partner Iddo Goldberg at a ceremony in the English countryside this weekend.
A reboot of Dallas starring Jesse Metcalfe, Josh Henderson, Larry Hagman and Patrick Duffy premiered on TNT in the US last Wednesday (June 13).
Watch Emily VanCamp talk to Digital Spy about Revenge below: