Zambian author, Namwali Serpell, who , has promised to share her £10,000 ($15,600) cash prize with the four runners up..
Serpell won the prize for her story 'The Sack', beating 4 other writers, including two Nigerians; Elnathan John and Segun Afolabi, to emerge the winner.
The judges described her action as "innovative, stylistically stunning, haunting and enigmatic".
Speaking about her decision, Serpell described her action to BBC Newsday as "an act of mutiny".
"I wanted to change the structure of the prize". she said.
"It is very awkward to be placed into this position of competition with other writers that you respect immensely and you feel yourself put into a sort of American idol or race-horse situation when actually, you all want to support each other."
Previous Nigerian winners of the prize are: Helon Habila (2001), Segun Afolabi (2005), E.C. Osondu (2009), Rotimi Babatunde (2012) and Tope Folarin (2013).