Not the first time he's mentioned his dislike for the pop star.
In the new edition of "Live From New York: An Uncensored History Of Saturday Night Live," written by James Andrew Miller and Tom Shales, Hader doesn't hold back when talking about his experience working with the 20-year-old "Baby" singer.
"I really didn't enjoy having Justin Bieber around," he said, via Hollywood Life. "He's the only one who lived up to the reputation. I think that's the only time I felt that way in eight years."
Fellow "SNL" cast member Kate McKinnon also revealed that Bieber wasn't exactly thrilled with her now famous impression of him.
"Bieber wasn't too upset by my impression of him. But he wasn't pleased," she shared.
She later added, “He wasn’t pleased” that the cast didn’t like him very much. However, he failed to change his diva attitude, ultimately making him the worst host in "SNL" history.
Last May, Hader also mentioned his distaste for Bieber's diva antics during an interview with Howard Stern.
"Justin Bieber showed up with like 20 guys. He had a guy holding a slice of pizza. A guy holding a diet coke," he laughed, comparing him to Justin Timberlake, who came in with a different attitude and entourage. "Going around stage, you're trying to fight through all these people to get dressed."