The Almost Famous actress plays Cassandra July, Rachel Berry's catty New York dance instructor.
People reports that at the recent premiere of the Fox show at Paramount Studios in LA, Hudson admitted: "Being that mean for me, it's pretty difficult. It was challenging to keep a straight face."
Hudson's character has made Rachel Berry's (Lea Michele) transition a tough one in the season four premiere.
"I think she sees Rachel as this young, talented, cute girl, and she's just sort of bitten with jealousy and wants to make her life a bit miserable," Hudson added.
Glee continues on Fox on Thursdays at 9/8c.
Watch Glee cover One Direction's 'What Makes You Beautiful' below: