The award was voted by the fans through RedTV, and Aberdeen Mad and AFC's local radio partner Northsound.
Voting was close this year with a good number of players in contention but the Dons central defender came out on top.
Reynolds told RedTV: "I am absolutely delighted. There were a lot of contenders this season because we have had a successful year.
"We have won our first trophy for 19 years, we are pushing for second place so it have been a massive turnaround. To do that we have need players to step up their games and everyone has done that.
"It is a great honour because it has been voted for by the fans. I would like to say a massive thanks to them. The fans make the club. They are the lifeblood of football so it is great to get the recognition from them.
"The whole season has been a very enjoyable journey and now it is down to one game. Hopefully we can get the win and finish the season on a high."
Other awards went to: Jonny Hayes (Goal of the Season); Craig Murray (U20 of the Year); Peter Pawlett (Player's Player of the Year); Nicky Low (Young Player of the Year); and Stewart Milne (Special Recognition Award).
Read all about the awards and see more photos on RedWeb, and watch a video of the full Reynolds interview on RedTV.
Image: Newsline Scotland