The 20-year-old forward is the first player to win the new award from the BBC World Service, voted for by football fans around the world.
She beat Spain’s Veronica Boquete, German Nadine Kessler, Scot Kim Little and Brazilian Marta to the honour.
“I would like to say thank you to the BBC, to my fans around the world and to everyone who voted,” she said.
The award is the first of its kind hosted by a global broadcaster.
Oshoala, who was the youngest player to be shortlisted, was the leading scorer at the Under-20s World Cup in Canada last summer and was voted the tournament’s best player.
Her performances led Nigeria to the final, where they were narrowly beaten by Germany, and she was also a major influence in the senior Nigeria team who won the African Women’s Championship in October.
Read more at: BBC Sport