The Celtic attacking midfielder has scored 28 goals across all competitions for the Scottish Premiership champions this season.
Commons finished ahead of his Hoops team-mates Fraser Forster and Virgil van Dijk as well as Kilmarnock striker Kris Boyd, it was announced at the awards dinner held in Glasgow.
Aberdeen boss Derek McInnes was named manager of the year while Dundee United's left-back Andy Robertson was voted young player of the year.
Kane Hemmings of Cowdenbeath picked up the Championship award while Rangers left-back Lee Wallace was voted the best player in League One with Peterhead's Rory McAllister winning the League Two award.
McInnes, who guided Aberdeen to their first piece of silverware with the League Cup final win over Inverness in March said: "It is testament to the effort of the players, it shows what can be done with a hungry group of talented boys.
"My assistant manager Tony Docherty has been invaluable to me, and the rest of my staff, so the award is as much for them as for me."
McInnes, whose side are second in the Scottish Premiership, four points ahead of Motherwell with three games remaining, continued: "It is nice to see Aberdeen as a club in a positive light.
"I was at an awards dinner last season and we hardly got a mention and it made me really aware that there was a lot of work to be done.
"We have had a lot of awards this year, a lot of plaudits so I think that shows how where we have come from as a club and hopefully this time next year there will be something similar again.
"The cup win was needed by the club and the city, the players have enjoyed that success and I think that has whetted their appetite to be successful in the cups again.
"We can't be satisfied with that we have done, I would like to think there is still more to come from us.
"We are not obsessed with finishing second, we just wanted to make sure we improved but now that we are here, with three games to go we want to secure European football.
"Hopefully we can get the points to get European football and if we can move on to second then so be it."
A delighted Robertson earned yet another accolade in an remarkable first season in the top flight.
The 20-year-old defender moved from Queen's Park to United only last summer and a meteoric rise saw him pin down a regular starting berth right away at Tannadice and win his first Scotland cap in the friendly against Poland in March.
However, with the William Hill Scottish Cup final to come against St Johnstone at Celtic Park next month, Robertson has a chance to put the icing on the cake.
He said: "It has been a really successful season for me but this award probably means the most to me, because the players have voted for me.
"If we could win the Scottish Cup that would top off the most amazing season for me.
"We know it will be tough against St Johnstone but we will try to get the win on that day.
"We let ourselves down in the league last week by getting beat in the league by St Johnstone but we were magnificent against Motherwell in the 5-1 win on Saturday.
"The Scottish Cup final will be completely different with the fans, the atmosphere and what is at stake."
Robertson beat off United team mates Stuart Armstrong and Ryan Gauld, as well as St Johnstone striker Stevie May, to win the award.
He said: "Stuart and Gauldy have had amazing seasons but I am glad to win it.
"We have been joking since we were nominated and there was a few laughs.
"I wouldn't say we were really surprised when the three of us were nominated because we were playing well as a whole team but there has to be credit given to the other players like Paul Paton and John Rankin, who have played every week and made us tick."
Aberdeen's Jonny Hayes won the goal of the season award for the strike against Celtic in February.