Rep. George Santos ain't Rosa Parks, despite comparing himself to the civil rights pioneer -- so says the icon's niece ... telling GS to keep her name out of his mouth.
Rhea McCauley tells TMZ ... she felt it was totally inappropriate for Santos to compare himself to her aunt, saying it's apples to oranges when it comes to the situation. She also says other family members related to Parks are pretty pissed about his remarks too.
In other words, he seemed to be suggesting ... he wouldn't either, likening himself to her.
McCauley says she and the rest of the fam are ticked off that Santos even brought her up, pointing out that his juxtaposition here isn't even historically accurate -- namely, on account of the fact that Parks was fighting against segregation ... and that George seems to be airing out a petty feud between himself and another politician. Not really the same thing.