The 25-year-old Algerian international, the first Leicester player and first African to win the award, has scored 17 goals and made 11 assists in 34 league games to help Leicester move to the brink of their first English top-flight title.
Mahrez finished ahead of fellow Leicester players Jamie Vardy and N'Golo Kante, Tottenham Hotspur striker Harry Kane, Arsenal’s Mesut Ozil and West Ham United's Dimitri Payet.
The Algerian praised the contribution of his team mates and manager Claudio Ranieri after being voted the best player in England by his fellow professionals.
“All the credit is for them, seriously,” Mahrez, who joined Leicester from French second-tier side Le Havre in January 2014, said.