The 23-year-old former Dundee United and West Brom player beat off competition from Hearts trio Jamie Walker, Margaro Gomis and Alim Ozturk to win the award at a ceremony in Glasgow on Sunday evening.
Walker and Jambos team-mate Sam Nicholson were in the running for the Young Player of the Year award, along with Inverness forward Ryan Christie, but they were beaten to the prize by Celtic’s Jason Denayer, who is on a season-long loan deal from Manchester City.
Speaking to Sky Sports News HQ at the ceremony, Allan said: “It’s a really nice accolade to get voted for by your fellow professionals. Now we just look to the play-offs and hopefully gain promotion.
“I think it was vital psychologically for us to get second place. We hadn’t beaten Falkirk this year so to go and win 3-0 comfortably was good for us and it gives us that break now get players back fresh and ready to go.
“It was nice to win after that cup disappointment but we just need to focus on these play-offs and get up now. The bonus is not having to play for so long. It gives us time to get players fresh and ready to go again. Players that have niggling injuries to get them back.”
Asked if having fewer matches to negotiate gives his side the upper hand in the play-offs, Allan added: “I I wouldn’t say we were favourites but were a strong candidate.
“We’ve got the momentum now and the team we will play against might not have as much as us given the goals we have scored in recent games so I would say we are in with a chance anyway.
Declan McManus, on loan at Morton from the Premiership runners-up Aberdeen, won the League One award with Arbroath striker Bobby Linn lifting the accolade for League Two.
The top award of the evening went to Celtic midfielder Stefan Johansen while Inverness boss John Hughes, whose side face Falkirk in the final of the Scottish Cup later this month, was named manager of the year.
The Goal of the Season went to to Stephen Mallan of St Mirren while Jordan Moore of Dundee United was presented with a Special Merit Award.
The young player has successfully battled cancer and is now raising money for charity as well as resuming his career.