Lively stars opposite Ryan Reynolds in the Warner Bros adaptation as Hal Jordan's love interest Carol Ferris, a character who becomes the supervillain Star Sapphire at various points in the comic book history.
The Gossip Girl actress said that she believes her role as a drug addicted mother in last year's The Town convinced the producers of Green Lantern that she would be able to play a good character who still has the potential for evil.
"I think that they saw from my role in The Town that I was able to be dark and angry, and be a villain," Lively said, according to Comic Book Resources.
"If this movie is successful and we do a few more films, I'm pretty confident that Star Sapphire would show up," Lively teased. "All the conversations are very guarded and protected, even with [the actors] because nobody wants to commit to anything, but I can't see Star Sapphire not showing up if we made more films."
Reynolds also admitted recently that he would be interesting in starring in more Green Lantern films.
Green Lantern is due to be released in US and UK cinemas on June 17.
Watch Blake Lively in the WonderCon footage of Green Lantern below: