The decision was made by the EFF this week, and was confirmed in a post from the party, showing Fana and other representatives of the party being sworn in on Tuesday.
Pictures of the ceremony were also posted by Fana on Facebook this week and show the smiling World War Z star taking his oath.
Speaking to TMG Entertainment on Thursday, Fana explained that he previously represented the party in the National Council of Provinces (NCOP) but will now fill his duties and responsibilities in the National Assembly.
"I will continue to attend debates and committee meetings but these will now be done as a member of the National Assembly," Fana explained.
The former Generations actor said that he is both "excited and honoured" by the opportunity given him and looks "forward to serving".