Ronaldo, who won the award last season, helped Real Madrid to a third consecutive Champions League title and finished as the competition's top scorer with 15 goals.
Ronaldo is a UEFA Champions League victor for a record fifth time and UEFA Champions League top scorer for the sixth campaign running.
The award typically rewards Champions League performances - with all three on the shortlist having played in the final in May - but voters can take the World Cup into account.
The stars are judged on their displays in all competitions, at domestic, continental and global level. The tournament in Russian Federation could prove to be Croatia's current golden generation last major worldwide appearance, and Zlatko Dalić's side shocked fans across the globe by reaching the final.
Luka Modric helped his nation reach the final of the 2018 World Cup in Russian Federation where he won the Golden ball award.
The award, which rivals the Ballon d'Or is run by UEFA and perhaps there in lies the reason for Ronaldo's preference over Messi.
The victor will be announced on August 30 in an official UEFA ceremony, which will also involve a draw for the group stages. He also won the Champions League title with Los Blancos.
The vote does not always reward a Champions League victor. He has also won the award on three occasions compared to Messi's two.
Varane is on an all-Madrid defenders list with Marcelo and Sergio Ramos, and the goalkeeper candidates are Alisson, Gianluigi Buffon and Keylor Navas.
UEFA has today announced the names of the nominees shortlisted for the 2017/18 UEFA Men's and Women's Player of the Year Awards.
The three players who received the most points overall from this voting procedure, in alphabetical order, are: Pernille Harder (Denmark - VfL Wolfsburg), Ada Hegerberg (Norway - Olympique Lyonnais), Amandine Henry (France - Olympique Lyonnais).