The actress appeared in Allen's 2007 movie Cassandra's Dream and is thought to play a larger role in the director's as-yet-untitled upcoming movie, which also stars Alec Baldwin, Cate Blanchett, Peter Sarsgaard and stand-up comedians Louis CK and Andrew Dice Clay.
"He's lovely. He's got high, high expectations, more often than not of himself," Hawkins told Digital Spy.
"It's a huge thing... you're like 'It's Woody Allen' and you can't ever stop thinking that because he's a phenomenon and has been for so many years."
She added: "I grew up watching his films. He's iconic. It is amazing. I just hope that it's okay. You learn so much from him. He's also this incredible dramaturg, he's an incredible writer.
> The Wonderful World of Woody Allen
"The way he thinks about the rhythm of the scenes and the words and the beat. He's always thinking about the audience and what's it going to be like. He's editing it as he goes.
"Each director you work with is always different and what I love about him is he's in his '70s now - he just keeps going.
"He's incredibly prolific. All he wants to do is write and keep going. It's forward motion. It's so inspiring. He just loves it and writing is what it's all about for him. He's beautiful."
Sally Hawkins and Rafe Spall star in Constellations, which runs Monday to Saturday at 7.30pm until Saturday, January 5, 2013 at London's Duke of York's Theatre, with Wednesday and Saturday matinees at 2.30pm.
Tickets are priced at £10, £25 and £37.50, and concessions and group discounts apply.