Parker, who is the first West Ham player to retain the award since Julian Dicks in 1995/96 and 1996/97, also scored outstanding goals at Chelsea and in the vital 3-2 Barclays Premier League victory over Wigan Athletic last month.
"It's been a fantastic season for me, personally," Parker told whufc.com. "We've had a lot of hard times as a team this year, but at the end of it, I suppose we're still in the Premier League.
"I know, at times this year, we've probably not given you the sort of things you deserve but I speak for the squad and the staff when I thank you all for your support.
"I want to thank the staff - Steve Clarke and Kevin Keen - for all the hard work they've done, and also I want to thank the manager, Gianfranco Zola, for having so much faith in me and giving me great belief."