The Welshman becomes the 15th player to win PFA and FWA honors in the same season, with Robin van Persie and Juan Mata completing the top three and Luis Suarez getting two votes.
Gareth Bale has been named as the Football Writers' Association Footballer of the Year.
The Tottenham star has completed a clean sweep of this season's individual awards, having already won the PFA Player of the Year and Young Player of the Year gongs last week.
Bale becomes the 15th player to be recognized by the PFA and FWA in the same season, garnering 53 percent of journalists' votes.
Robin van Persie finished second with 43 percent, while Juan Mata completed the top three.
Luis Suarez, currently serving a 10-match ban for biting Branislav Ivanovic, received only two votes, one more than Aston Villa striker Christian Benteke.