The majority of the population in Egypt is Muslim and the country is hugely conservative. Wearing revealing attire is not only frowned upon, but punishable by law.
The Daily Mail reported that Youssef could spend five years in prison if the court rules against her.
On Saturday, the actress posted her reaction to the backlash on social media. Her statement read like an apology.
She said the evening gown, made of embroidered gauze, was a creation by fashion designers who drew their inspiration from international film festivals.
“I want to repeat my commitment to the values and ethics we have been raised in in Egyptian society,” said Youssef.