The Leicester winger was ahead of his rivals with 361 votes which include last year's winner Pierre-Emerick Aubameyang of Gabon (313 votes) and Senegal forward Sadio Mane (186 votes).
Mahrez was seen as a key figure for Leicester last season, which saw the English East Midlands club defy 5000-1 odds and predictions of relegation to clinch a fairytale title victory.
He played in all but one of the Foxes' games in 2015-16 and scored 17 goals.
His fantastic form earlier earned him the PFA player of the season award.
Mahrez's clinching of the award ends a 19-year absence on the podium for a player from north Africa since Morocco's Mustapha Hadji in 1998.
Other Algerians to have won are Rabah Madjer in 1987 and Lakhdar Belloumi in 1981.
Elsewhere in the Maghreb, the title has gone to Morocco's Badou Zaki (1986) and Mohamed Timoumi (1985); Mahmoud Al Khatib (Egypt, 1983), Tarek Dhiab (Tunisia, 1977); and Ahmed Faras (Morocco, 1975) when the awards were organised by France Football magazine.