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.
He scored twice in a 4-1 win over Juventus in the continental final at Cardiff's Millennium Stadium on June 3.
Real boss Zinedine Zidane took the corresponding Manager of the Year award, with the Spanish giants providing five players in the FIFA 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.
This year he saw off competition from long-standing Barcelona rival Lionel Messi and Paris Saint-Germain's Neymar, with former Manchester United favourite Ronaldo receiving his trophy from Argentina great Diego Maradona and Brazil's Ronaldo in a star-studded ceremony at the London Palladium theatre.
"Thanks a lot for voting for me," said the Portuguese superstar.
"I mention Leo and Neymar, it's great to be here. Real Madrid supporters, my team-mates, my coach, they all support me all year.
"We are in England for the first time and I win consecutive awards," he added. "I am really glad, this is a great moment for me. I have fans all over the world."
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.
"I'd like to thank all of the players for making this possible," said Zidane. "This is a very special prize."
Real's superb campaign was recognised in a FIFA XI that featured Ronaldo and club-mates Toni Kroos, Luka Modric, Marcelo and Sergio Ramos.
The team was completed by goalkeeper of the year Gianluigi Buffon, Leonardo Bonucci, Dani Alves, Andres Iniesta, Messi and Neymar.
Giroud wins best goal
Veteran Juventus and Italy shot-stopper Buffon topped a three-strong shortlist for the Goalkeeper Award ahead of Real's Keylor Navas and Bayern Munich's Manuel Neuer.
"I have to speak in English, it is a difficult moment," said the 39-year-old Buffon.
"It is a great honour to receive this award at my age. I am proud.
"The last year has been fantastic for Juventus and for me personally. It wasn't enough to win in Europe.
"I would like to finish with a fantastic victory for Italy next summer (at the 2018 World Cup in Russia)."
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.
The Frenchman's flicked volley with his left foot that went in off the crossbar won ahead of goals from Venezuela's Deyna Castellanos, 18, and South African goalkeeper Oscarine Masuluke.
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.
Wiegman and Martens were unable to receive their awards in London as the Netherlands are playing Norway on Tuesday.
The voting for the Best FIFA awards, equally weighted between national team captains, national team coaches, media and fans, closed last month.