The "Beetlejuice Beetlejuice" star sat down for a new interview with the Times and said Jen's recent beef with Donald Trump's running mate J.D. Vance had him in his feelings over his ex.

Justin told the Times of Jennifer ... "She is still very dear to me so, of course, yeah, I feel protective."

He was responding to questions about Jennifer's public spat with J.D. over Vance's controversial childless cat lady remarks.

Justin added ... "But she batted back criticism, as well she should."

Unclear how the interview is going to go over with Justin's new fiancée Nicole Brydon Bloom ... they just got engaged last month in Italy during his promotional run for his new movie.