Salah and Manchester City's Kevin De Bruyne had been frontrunners for the award but the Egyptian has pipped him by less than 20 votes.
The Egypt worldwide has scored 43 times in all competitions, including 31 in the Premier League to equal the record haul for a single 38-match season.
The Reds forward joins Ian Callaghan, Kevin Keegan, Emlyn Hughes, Kenny Dalglish (twice), Terry McDermott, Ian Rush, John Barnes (twice), Steve Nicol, Steven Gerrard and Luis Suarez in winning the award while representing Liverpool.
With Mohamed Salah just one goal from making history and becoming the highest scorer of all time in a 38-game Premier League season, a suspension at this point would be devastating.
Meanwhile, Tottenham Hotspur striker Harry Kane came third although Salah and De Bruyne tallied over 90 percent of the popular vote.
PM Modi silent even as democratic institutions are under attack: Rahul
Amethi MP said Modi still campaign that the Congress did not do anything in 70 years and he can change the country in 60 months. Singh also showed his concern for protecting the democracy of the nation and said, "Democracy is a gift of the Constitution".
He is now available to face former club Chelsea on Sunday and Brighton in Liverpool's final Premier League fixture of the season on May 13.
Salah will head to the World Cup in Russian Federation in June to play for Egypt who have been drawn with the hosts, Saudi Arabia and Uruguay in Group A.
Sergio Aguero, Christian Eriksen, Roberto Firmino, David Silva, Raheem Sterling, Jan Vertonghen and Nick Pope were the other players in contention for the award. But Mo Salah is the worthiest of winners. "He is also the first African to receive the award and we congratulate him on a magnificent season", FWA Chairman Patrick Barclay said.
And speaking ahead of Wednesday's match at the Stadio Olimpico, Klopp believes Salah's spell in the Italian capital helped his career to flourish.