Lupita Nyong'o, who landed the role after her impressive film debut last year, will be joined by epic fantasy programme Game of Thrones actress Gwendoline Christie.
Christie also has a role in eagerly-anticipated The Hunger Games: Mockingjay - Part 2.
The new cast-members are set to join original members of the first Star Wars trilogy, including Mark Hamill, Carrie Fisher and Harrison Ford.
The president of production company Lucasfilm, Kathleen Kennedy, said: "I could not be more excited about Lupita and Gwendoline joining the cast of Episode VII.
"It's thrilling to see this extraordinarily talented ensemble taking shape."
The eagerly anticipated Episode VII, which began production last month, is set to be released in 2015.
Other actors confirmed for the film include Daisy Ridley, Oscar Isaac, Andy Serkis and Domhnall Gleeson.