Harry Potter star Julie presented the Grand Prize, and the £30,000 film funding bursary, to Jennifer Sheridan for her film Rocket, about a dog who dreams of going into space and builds his own spaceship.
Julie said: "Rocket really captured my imagination and I connected with his plight to escape the bright lights of the city.
"I'm looking forward to seeing what Jennifer will produce next and getting a cuddle with the leading man."
The film starred Jennifer's pet dog Bowie, but some of the other shortlisted films this year boasted star names among their cast.
Man Up, by Carolina Giammetta, starred Nick Moran sending up his own hardman film image in a sketch about blokes in the pub discussing how to impress their wives with cooking and sewing skills.
Love story Little Larry, by Andrew Lee Potts, featured former S Club 7 star Hannah Spearritt, funeral comedy Mourning Rules by Dan Castella boasted The Thick Of It's Olivia Poulet and Holby City's Joseph Millson among its cast and Skirt by Amanda Boyle starred Julie's own Harry Potter co-star Natalia Tena.
The People's Choice Award went to director PJ Liguori for his visual piece PJ, Tiny Planet Explorer and the TiVo Award was won by Dream Girl from Alice Seabright, about a girl falling asleep on the train.
Guests joining in the celebrations at the BFI included Daisy Lowe, who took a turn in the DJ box, Joseph Mawle and Matt Milne.