The "Hustlers" star, who walked the red carpet with fiance Alex Rodriguez, opted for a white, voluminous gown that included a massive gold-and-green bow.
"Nooooo..to the dress Awful!" one user tweeted.
Another said, "I LOVE LOVE LOVE Jennifer Lopez, but tonight’s gown is a mess. The braided bun is a NO, too. It hurts me more to even type this."
A few Twitter users compared the dress to gift wrap.
"Okay. I feel like Jennifer Lopez got a really cool, really big Christmas present, fell in love with the gift bow and wanted her stylist to incorporate it into tonight’s ensemble."