A plastic poncho, a chainmail crop top and tights with stirrups -- stars are rocking all the wrong trends this week!

Lady Gaga -- aka the Queen of toodrab -- landed on our worst dressed list this week for donning a plastic poncho to give the Keynote speech at SXSW in Austin, Texas on Friday.

While the "Art Pop" singer is no stranger to sporting weird ensembles, she should take her speaking gig more seriously! Is it ever appropriate for the guest of honor to wear an oversized plastic frock onstage? 

Kim Kardashian raised eyebrows at the opening of DASH Miami Beach on Wednesday, donning a see-through crop top and matching pencil skirt made out of what appears to be chainmail (or some other metallic material). Come on, Kim, that can't be comfortable!

And, Sarah Jessica Parker caught everyone's attention at the launch of her shoe line "SJP" at Nordstrom in Aventura, Florida -- and not in a good way.

The former "Sex and the City" star should know better than to wear tights with stirrups and an awkward dress-over-shirt combo.

But they weren't alone -- see more of this week's worst dressed stars in the gallery above!