"I'm a little overwhelmed," said Fotu-Moala.
"I was speechless when I heard my name read out.
"I don't think it has sunk in yet. It's a massive World Cup and it's quite competitive this time so I'm really honoured to say the least."
Australian captain Cameron Smith has also been crowned the Golden Boot winner ahead of Saturday's World Cup final against England.
The 34-year-old Smith beat out Tongan star and former Kiwis test forward Jason Taumalolo, England's Jermaine McGillvary, and Fijian wing Suliasi Vunivalu to claim the award for the second time after winning his first Golden Boot in 2007.
Smith's triumph comes towards the end of what has been a dream season for the Kangaroos hooker, after leading the Storm to a NRL grand final win over the Cowboys and the Maroons to a series win over New South Wales, while he also won the Dally M award and topped Darren Lockyer's record as the most-capped player in the NRL.
"It's obviously been a fairly successful year for myself but we're playing a team game and it's not an individual sport at all," said Smith.
"I've been very fortunate along the way throughout this entire year that things have fallen into place for myself with some of the performances that I've put in.
"But I've got to say a massive thank you to all of my teammates throughout the season, not only at the Storm but with Queensland and the Kangaroos as well."