The actress, who is dating singer Justin Timberlake, admits she and the "Pretty Woman" star bonded instantly on the sets of their new movie "Valentine's Day" and she just can't bear to be out of contact with her, reports femalefirst.co.uk.
"I definitely have one (girl crush) on her. I think she is amazing. Although I did panic for a while because I sent her a text and she didn't reply for a while. But we're fine now," said Biel.
Apart from her feelings for Julia, Biel has previously also admitted to having a crush on another of her "Valentine's Day" co-stars Jennifer Garner.
The movie is releasing worldwide Friday.