Mane was in impressive form for Jurgen Klopp's side last month with two goals in four Premier League outings.
The 26-year-old found the back of the net in Liverpool's 4-3 win over Crystal Palace and in their 1-1 draw against Leicester City as they registered a record of two wins, one defeat and a draw in all the games he played in January.
Mane, scorer of 12 league goals in 24 matches this term, beat off challenges from attacking partners Salah and Roberto Firmino to claim the accolade.
Mane, Salah and Firmino have continued their dreadful combination this season with the trio notching 38 league goals between them so far.
The Senegal international was in action in the Reds' Uefa Champions League goalless stalemate against Bayern Munich on Tuesday and he will hope to return to the score sheet when the Anfield outfit visit Manchester United for Sunday's Premier League fixture.