Nacewa has featured in all but one of Leinster's games this season and has won rave reviews on his performance in virtually every game.
"I'm just overwhelmed," he said.
"It's such an honour.
"I think it's one of the top awards you can get as a player, and something that is voted on a lot over the years. So, very over-whelming to get it, considering it (the list of previous winners) is a who's who of Irish rugby."
In other awards Malcolm O'Kelly was inducted to the Hall of Fame and Richardt Strauss won the Unsung Hero Award. Ulster centre Nevin Spence was voted young player of the year while Connacht wing Fionn Carr was awarded the Try of the Year.
IRUPA AWARDS
Players' Player of the Year: Isa Nacewa (Leinster). Young Player of the Year: Nevin Spence (Ulster). Unsung Hero Award: Richardt Strauss (Leinster). Hall of Fame: Malcolm O'Kelly (Leinster). Try of the Year: Fionn Carr (Connacht, away to the Scarlets). Supporters' Player of the Year: Seán O'Brien (Leinster).
63x46.png){kind=logo}