An investigation is underway after bullet holes were found in Mana leader Hone Harawira's Kaitaia electorate office.
Shots were fired through the office's front window last Thursday night, Mr Harawira told Radio New Zealand.
He said he was taking the threat seriously.
"It is a worry, I get criticisms, I get threats - I even get death threats - but when people start taking shots at your office it's a whole different ball game.
Hopefully they'll catch the shooter, and I look forward to their prosecution. This sort of thuggery has no place in our political system.