Jolie met with earthquake victims and toured a field hospital set up by the medical aid group Medecins Sans Frontieres (MSF) in a suburb of Port-au-Prince, waving to onlookers who shouted "Angelina!"
Jolie and her partner Brad Pitt have contributed $1 million to MSF, also known as Doctors without Borders, for its emergency medical operations in Haiti.
Jolie also visited an SOS Children's Villages center for orphans outside the capital.
It was the same orphanage that took care of 33 Haitian children after members of a U.S.-based Baptist group were arrested at the border with the Dominican Republic for trying to smuggle them out of the country.
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It wasn't known if Jolie spoke with any of the children, and journalists were kept at a distance throughout her visit.
Jolie also attended a meeting with acting U.N. Special Representative for Haiti, Edmond Mulet and senior U.N. staff at their headquarters near the capital.
She met with Haitians employed in quake debris cleanup through a joint U.N.-U.S. Agency for International Development program before spending the night at a Brazilian military camp outside the city.
On Wednesday, Jolie planned to visit the southern city of Jacmel, a camp for people made homeless by the quake, as well as a Save the Children relief supply centre before returning to Port-au-Prince and leaving for the neighboring Dominican Republic.
Jolie has previously visited Iraq, Thailand, Pakistan and other countries with UNHCR. On Monday she visited children injured by the earthquake in a hospital in the Dominican Republic.