Striking duo Luis Suarez and Daniel Sturridge have scored 49 league goals between them this season, with Uruguay international Luis Suarez leading the Premier League scoring charts with 29 goals for Brendan Rodgers' table-topping side.
Captain Steven Gerrard, 33, has contributed 13 league goals and 11 assists for Liverpool F.C. this season with the England midfielder aiming to lift his first Premier League title.
With four games left Liverpool F.C. have a two-point advantage over second-placed Chelsea, whose Belgium forward Eden Hazard is also among the nominations for player of the year with Ivorian Yaya Toure (Manchester City) and Adam Lallana (Southampton).
Sturridge and Hazard were also shortlisted for young player of the year, the PFA said on its website (www.thepfa.com), along with Liverpool's England winger Raheem Sterling, Ross Barkley (Everton), Aaron Ramsey (Arsenal) and Luke Shaw (Southampton).
Gareth Bale won both awards last year playing for Tottenham Hotspur before his world record transfer to Real Madrid in the close season following in the footsteps of Andy Gray (1977) and Cristiano Ronaldo (2007) who also achieved that feat.