Billie Eilish had no filter after running into a Sports Illustrated model at the Golden Globes ... bluntly telling her "You're hot as balls" during their hilarious interaction.
Former NFL lineman Matt Kalil's stunning ex-wife, Haley, was doing social media content for the annual awards show on Sunday ... and at one point in the night, she ran into the superstar singer.
"Billie, can I just say I am literally obsessed with you," the influencer said in a video of their convo.
Eilish -- who won Best Original Song for Barbie's "What Was I Made For?