The Portuguese ace, who has scored 44 goals in just 48 games for club and country so far this calendar year, played a major role in Real winning both La Liga and the Champions League.
Ronaldo saw off competition from longstanding Barcelona rival Lionel Messi and Paris Saint-Germain's Neymar, the world's most expensive player.
Real boss Zinedine Zidane took the corresponding manager of the year award, with the Spanish giants providing five players in the FIFPro team of the year.
Ronaldo won the inaugural Best Fifa men's player of the year award last year following the end of a six-year merger between the Fifa honour and the Ballon D'Or. The 32-year-old previously won the Fifa World Player of the Year award, the precursor to the Best Fifa award, in 2008.
"Thanks a lot for voting for me," said the former Manchester United favourite after receiving his trophy from Argentina great Diego Maradona and Brazil's Ronaldo at the London Palladium theatre. "I mention Leo and Neymar, great to be here. Real Madrid supporters, my team-mates, my coach, they all support me all year."
Zidane won out ahead of Chelsea's Antonio Conte and Juventus's Massimiliano Allegri to be crowned men's coach of the year after becoming the first man to oversee a successful defence of the European Cup in the Champions League era.
Real's superb campaign was recognised in a FIFPro team that featured Ronaldo and club-mates Toni Kroos, Luka Modric, Marcelo and Sergio Ramos.
The XI also included Fifa's goalkeeper of the year, Gianluigi Buffon. AC Milan's Leonardo Bonucci and PSG's Dani Alves were in the defence, with Barcelona playmaker Andres Iniesta in a side also featuring Messi and Neymar.
Best goal for France
Monday also saw the Puskas Award for the best goal of 2017 go to Arsenal's Olivier Giroud. The France striker received the award named in honour of Hungary great Ferenc Puskas for a spectacular 'scorpion-kick' against Crystal Palace in January.
"I'm delighted to receive this trophy today in front of legends of football," said Giroud.
Meanwhile tournament hosts the Netherlands' achievement in winning their first major female football title, the 2017 Women's European Championship, was recognised with Women's Coach of the Year and Player of the Year awards for Sarina Wiegman and Lieke Martens respectively.
Supporters of Celtic won the Fan Award for the way they marked the 50th anniversary of the 'Lisbon Lions' European Cup triumph that saw the Glasgow side become the first British club to lift the trophy after they beat Inter Milan in the Portuguese capital.
The Fair Play award went to Francis Kone for saving the life of goalkeeper Martin Berkovec, who nearly suffocated as a result of swallowing his tongue during a Czech league match in February.