The Wales international, 23, topped the poll of journalists with a narrow victory over Manchester United's Dutch international forward Robin van Persie, who won it last year when he was at Arsenal. Chelsea's Spanish midfielder Juan Mata came third.
Luis Suarez's heroics for Liverpool did not even earn him a place in the top three, as Bale and van Persie scooped 96 per cent of the votes.
Bale is the first Spurs player to win the world's oldest individual award since David Ginola in 1999 and the first Wales international to claim it since Everton goalkeeper Neville Southall in 1985.
"I've been very fortunate to play in such a fantastic team and I owe a lot to my team-mates and obviously the manager who has shown such faith in me," Bale told the FWA.
FWA chairman Andy Dunn said: "In a contest for votes that took so many late twists and turns, Gareth's penchant for the spectacular captured the imagination.
"He is a player who is rising inexorably towards the rarefied levels of world stars such as Lionel Messi and Cristiano Ronaldo. Lets hope he lights up the Premier League for many seasons to come."
Bale has scored 24 goals in all competitions for Spurs and five for Wales, many of them spectacular strikes from outside the penalty area.
His performances helped Tottenham reach the Europa League quarter-finals and have kept them in the race for a top-four finish in the Premier League and a possible return to the Champions League.
He will receive the prestigious FWA trophy at a gala dinner in London next Thursday.
The award completed a personal treble for Bale who on Sunday was also named Player of the Year and Young Player of the Year by his peers in the Professional Footballers' Association. He also won the Player of the Year Award in 2011.
The Footballer of the Year award is the oldest of its kind in world football and was first given to Stanley Matthews in 1948.
Meanwhile, Andre Villas-Boas says he has been assured that Bale will stay with Tottenham this summer - even if the club do not qualify for the Champions League.
"The information that I have from the club, which was mistakenly written about last week, is that the player is here to remain, independent of the objectives of Champions League qualification being achieved or not," Villas-Boas said.
"I would be extremely surprised (if he left).
"In football anything can happen. It's impossible to predict, but this is the assurance I have had from the club.
"We understand that the more awards the more recognition the player will have, the more media attention, but the club has to move forward by holding onto its best players.
"With the recognition and the further experience that he has had from this year, next year for Tottenham he will be even more assertive."