Last year, the star called organisers "corrupt" after his album After Hours failed to receive a single nomination.
He took particular exception to the so-called "secret committees" who dictate the shortlisted nominees.
On Saturday, the Recording Academy announced they'd been scrapped - but The Weeknd said that was not enough.
"The trust has been broken for so long between the Grammy organisation and artists that it would be unwise to raise a victory flag," said the star, whose real name is Abel Tesfaye, in an interview with Variety.
