McKayla Maroney Thanks Michael Phelps ... You're the NEW Meme King!!!

Finally, McKayla Maroney IS impressed -- telling TMZ Sports she loves the new Michael Phelps death stare meme ... and says it takes her spot as the BEST Olympic funny face.

Of course, Maroney became a viral LEGEND back in 2012 thanks to the whole "not impressed" thing -- so, we had to hit her up to get her take on the new Phelps pic taking the Internet by storm.

"I now see why people thought (the memes were) so funny," Maroney says.

"Somebody tweeted like, 'McKayla looks like somebody took your spot' ... and I looked at his pictures and was like YES! Go Michael, take it away please!"

Looks like she got her wish!