The 33-year-old utility back is the Premiership's top points scorer this season, with his side topping the regular season table.
Owen Farrell - who can also play 10 or 12 - is the England men's player of the year after helping his side to back-to-back Six Nations titles.
Tamara Taylor took the women's prize after their Grand Slam.
Former New Zealand fly-half Dan Carter - the all-time leading points scorer in Test history - was inducted into the Hall of Fame.
Fellow New Zealander Gopperth, who has played at both fly-half and inside centre this season, topped the Premiership points charts with 266 as Wasps ended the regular season top of the table for the first time.
"I'm very humbled and surprised to win this award and I am even more proud of the recognition shown by my fellow players," he said.
"I am very lucky to be a part of such a driven and successful club and my team-mates deserve this award as much as I do.
"I'm sure I will look back at this moment down the track and be extremely proud."
Former Harlequins' forward Nick Easter, who retired from rugby last year, was given the special merit award.
Award winners in full:
Players' player of the year: Jimmy Gopperth (Wasps)
Young player of the year: Zach Mercer (Bath)
Championship player of the year: Mark Bright (Ealing Trailfinders)
Sevens player of the year: Richard de Carpentier
Special merit award: Nick Easter
Personal development programme: Nick De Luca (Wasps)
Blyth Spirit Award: Paul Van-Zandvliet
England men's player of the year: Owen Farrell
England women's player of the year: Tamara Taylor
Wasps' Jimmy Gopperth has been named players' player of the year at the Rugby Players' Association awards.