Julia Garner — who has been tapped to play Madonna in her upcoming biopic — shows she’s got the Material Girl vibe … showing up at a drag show, and even getting in on the action!

Drag Queen Ginger Douglas tells TMZ … Julia was having a blast at Mickey’s in WeHo during a performance of “Showgirls,” put on by “RuPaul‘s Drag Race” star Morgan McMichaels.

Julia, her hubby Mark Foster from Foster The People and the rest of her pals sat front row … Morgan even pulled her up on stage, congratulating her for her Madge flick … and the crowd went wild.

Julia stayed for the whole show — feeling the performances and even tipping the drag queens. She stayed after the show to take pics with members of the audience and some of the performers.