The grand prix-style, 18-event world tour – which would rival the PGA Tour – would feature 48 top players and have a $240m (£183m) total prize-fund.
Tiger Woods and Justin Rose both say they have been approached about the new format, which has divided opinion.
“The more I’ve thought about it the more I don’t like it. For me, I’m out,” said 30-year-old McIlroy.
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The British-based World Golf Group unveiled plans in January for Premier Golf League, which it hopes to launch in 2022.
PGA Tour commissioner Jay Monahan has told players they would have to choose between the new series or the PGA Tour, while European Tour chief executive Keith Pelley also issued a warning to those on that tour.
Fifteen-time major winner Woods said his team were looking at the plans, while Olympic champion Rose said there are “a lot of incentives for the guys to be interested”.
McIlroy, however, says he values having “autonomy and freedom over everything that I do”.
Speaking before the WGC-Mexico Championship, the Northern Irishman added: “This is a perfect example. Some guys this week made the choice not to come to Mexico. If you go and play in this other golf league you’re not going to have that choice.
“I read a thing the other day that said if you take the money they can tell you what to do, so if you don’t take the money they can’t tell you what to do.
“I think that’s my thing – I’ve never been one for being told what to do and I like to have that autonomy and freedom over my career and I feel I would give that up by going to play this other league.”