The 'Eat, Pray, Love' actor - who recently married long-term partner Penelope Cruz in a secret ceremony - felt like a teenage girl when he met the 'Inglourious Basterds' star because he couldn't believe how handsome he was.
He told Elle magazine: "I had the great opportunity to meet Brad Pitt a couple of times. what a beauty. He is beautiful and his physicality is so amazing to see.
"But the beauty really comes from different places - the way he talks, the way he's interested in what you're saying. And that body is like - wow! It's amazing, no? He really made me feel very, like. I don't know, like, I could fall in love with him!
"Like a teenage girl getting crazy and screaming like that. I met him only twice, but he was so nice, so generous and very true to himself, and I don't know him that well, but I would say it's a good self. And that is when the beauty comes, voom! And if you have a body besides that, then it's like, 'F**k!' "
Just as Javier is full of praise for Brad Pit, the 41-year-old Spanish star has been praised by his castmates for being a fun-loving guy.
Recalling a trip to a karaoke bar with Javier and Woody Harrelson, 'No Country For Old Men' actor Josh Brolin said: "We were at a Cowgirl BBQ, and Javier got up and sang karaoke. Spaniard that he is, he was singing and dancing all over the stage. He stage-dived at one point! Woody and I couldn't believe it. We were laughing so hard we were on the floor. Javier has an inner diva - some Barbra Streisand or Mariah Carey inside him."