The illustrious former Great Britain internationals are the latest players to join the prestigious roll of honour.
Loose forward Turner - who died aged 82 in 2015 - was captain of the all-conquering Wakefield Trinity team of the 1960s having started out at Hull KR.
He was part of Great Britain's World Cup-winning side of 1960 and later coached Castleford to Challenge Cup glory in 1969 before leading Leeds to the Championship three years later.
Fellow back-row Whiteley, 87, led Hull FC to two Wembley finals, as well as enjoying Ashes-winning success as a player and coach.
Gregory, meanwhile, was a multiple Challenge Cup winner with Widnes and Wigan and another famous Lions tourist.
Whiteley and Gregory will be joined by their families at the Rugby League Hall of Fame and RLIF Golden Boot dinner at Elland Road, Leeds, on Wednesday November 7.
It will also be attended by current Hall of Fame member Neil Fox MBE, Billy Boston MBE, Lewis Jones, Garry Schofield OBE and Malcolm Reilly OBE, as well as family representatives of Jim Sullivan and Mick Sullivan.
Chris Rostron, the Head of Rugby League Cares, said: “Hundreds of thousands of players have played Rugby League since 1895 and Johnny, Derek and Andy represent the best of the best.
“The three players had stellar careers and quite rightly deserve their place in Rugby League’s Pantheon alongside the existing 25 members of the Hall of Fame.
“It is an enormous honour and privilege for Rugby League Cares to have the responsibility of hosting the Hall of Fame dinner and we are looking forward to celebrating the sport’s greatest heroes at what will be a very special event.”
The Rugby League Hall of Fame is the highest honour any player can aspire to and has been awarded to just 28 players since the sport’s inception in 1895.
To qualify for membership of the Hall of Fame, a player must meet stringent criteria including a record of outstanding achievement at the very highest levels of the game; have a reputation that transcends the era in which he played; and made a contribution to the game that will last as long as rugby league is played.
Players are only considered for inclusion once they have been retired for 10 years; they must also have played at the highest level of Rugby League for a minimum of 10 years.
Members of the public are invited to help celebrate the induction of Johnny Whiteley, Derek Turner and Andy Gregory into the Rugby League Hall of Fame and RLIF Golden Boot Dinner, tickets for which are available priced Â£40.
To purchase tickets, please email [email protected]