He also signed a new contract at Old Trafford and make his European debut at home to Real Sociedad in the 1-0 win.
Januzaj told the club's website: "I'm really pleased to win this award, especially as it is voted for by the fans, who have been very supportive of me. So, thank you for voting for me.
"It's good to be recognised for your performances on the pitch but I realise that I have to work hard and keep progressing as a player.
"I will try to contribute to the team whenever I play and hopefully play my part in a successful season."
Januzaj will now donate a fee of £500 to a charity of his choice as part of winning award.
For breaking stories and all the great banter like us on Facebook: facebook.com/tribalfootball