The 24-year-old Victoria's Secret Angel rocked the plunging dress with a floaty bodice, bow at the back and a floor sweeping skirt.
She accessorized with peep-toe heels matching her dress, long lariat necklace and hoop earrings.
Her golden wavy locks were styled half up and half down with a swept up top. She wore shimmering silver eye shadow, thick liner on lids and fanned out lashes for a dramatic effect.
The British actress, accompanied by co-star Shia LaBeouf and director Michael Bay, greeted fans and signed autographs.
For Rosie and Team Transformers, Japan was the last stop of a promotional world tour, during which Rosie made impressive red carpet fashion statements at the film's premieres in countries across the globe, continuously varying her look and style, establishing her credentials as a fashionista who needs to be closely followed.
The film, which has already grossed more than $700 million worldwide, releases in theaters in Japan on July 29.