The /*United Nations*/ says 35-year-old Jolie is there in her role as "goodwill ambassador" for its refugee agency.
"I am very moved by them and I hope that I am able to, today and tomorrow, be able to do something to help bring attention to the situation for all of the people in need in Pakistan," Jolie told reporters after visiting a refugee camp in the Jalozai area.
She toured the area wearing a long black robe and a black headscarf adorned with a thin red stripe - the kind of conservative clothing worn by many Muslim women in Pakistan.
The flow of aid money has stalled in recent days, and officials expressed hope that Jolie's two-day visit will convince foreign countries and individuals to open their wallets.
There are no details on her itinerary.
The floods began in the northwest at the end of July after extremely heavy monsoon rains and slowly surged south along the Indus River, swallowing up hundreds of villages and towns and killing more than 1,700 people. Another 17 million have been affected by the floods, and many will need emergency assistance to survive.
The Associated Press contributed to this story.