The 19-year-old centre back from Brampton, Ont., is up against Norwegian forward Ada Hegerberg and Chinese midfielder Jiali Tang.
Buchanan, who attends the University of West Virginia, anchored a Canadian backline that conceded just three goals in five games.
Hegerberg scored three goals at the tournament while Tang helped pull the strings in the China attack.
Fifth-four players born after Jan 1, 1995, were eligible for the award. They were rated according to the following criteria: exceptional skill level, youthful and refreshing playing style, creativity and inspiration, tactical maturity and efficiency, fan recognition through entertaining performances, role model for young players, positive attitude and fair play.
Australia's Caitlin Foord won the award in 2011.
Canada, which exited after a 2-1 loss to England in the quarter-finals, was shut out of two other awards.
Canadian Erin McLeod, whom coach John Herdman touted as one of the best in the world, did not make the shortlist for the Adidas Golden Glove award that goes to the tournament's best goalkeeper.
The three 'keeper finalists are Germany's Nadine Angerer, Japan's Ayumi Kaihoro and American Hope Solo.
In five games at the tournament, McLeod had just 10 saves. But many were of the timely variety and the veteran 'keeper had three shutouts.
The finalists for the Adidas Golden Ball, which goes to the best player at the tournament, also did not feature a Canadian. The nominees are England's Lucy Bronze, France's Amandine Henry, Germany's Celia Sasic, Japan's Saori Ariyoshi and Aya Miyama, and Americans Julie Johnston, Carli Lloyd and Megan Rapinoe.
The Adidas Silver and Bronze Ball Awards will be presented to the second and third-best players.
The winners, as chosen by FIFA's technical study group, will be announced after Sunday's final in Vancouver between the U.S. and Japan. The Adidas Golden, Silver and Bronze Boots for the tournament's top scorers and the FIFA Fair Play Award will be announced at the same time.
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