The short belted sheath dress with a scoop neckline had a strap running down the middle of the bare back.
She accessorized with Christian Louboutin pumps, gold hoop earrings and twin heart ear studs.
She was accompanied to the event by co-star Shia LaBeouf and director Michael Bay; the three chatted with media and answered questions about the film that has already grossed $700 million worldwide.
In the evening, the trio attended the film's premiere.
The film will open in Japan on July 29.
This is Rosie's last international stop to plug her debut film.