Abbas met with Pakistan's president, General Pervez Musharraf, in Islamabad after a red-carpet reception and guard of honor.
He was to hold talks later with Prime Minister Shaukat Aziz.
Officials had no immediate details on the meeting between Abbas and Musharraf.
Pakistan is an Islamic state. It has no diplomatic ties with Israel and demands that the Jewish state end its occupation of Palestinian territory and give Palestinians the right to an independent homeland with Jerusalem as its capital.
Support for Palestinians
Earlier this week, Foreign Ministry spokesman Jalil Abbas Jilani said that Pakistan would continue "unequivocal and unreserved support to the Palestinian cause."
After a daylong visit to Pakistan, Abbas will travel to neighboring India. He made earlier stops on his regional tour in Japan and China.
Abbas heads to Washington next week for his first visit to the US since he was elected in January, and is to meet with US President George Bush on 26 May. He is expected to seek direct US economic assistance for his administration.