About 2,000 supporters outside the palace greeted the 61-year-old deposed leader with chants of Â"Gus! Gus!Â" his nickname.
He emerged from the palace with friends and family members who boarded vehicles in a motorcade bound for the airport, where Wahid will board a plane to Singapore en route to the United States.
The motorcade drove slowly through a sea of flag-waving supporters as guards cleared the way.
Wahid is expected to undergo medical treatment at Johns Hopkins Hospital in Baltimore, Md.
The national assembly sacked Wahid on Monday after impeaching him on charges of corruption and incompetence. They elected his deputy, 54-year-old Megawati Sukarnoputri, to succeed him.
Wahid initially refused to leave the palace, saying his ouster was illegal. He relented on Wednesday, apparently recognizing that he no longer had the support of the armed forces, the Parliament or the judiciary.
His departure came just hours after the legislature elected a conservative Muslim politician, Hamzah Haz, as the new vice president.
In an interview with The Associated Press and several other news media Thursday his last before leaving the palace Wahid said he had turned down an offer by Megawati to see him off at the airport, saying her ascension to the presidency was illegal.
Wahid said he will be one of the few voices for democracy in Megawati's Indonesia, which he said will be ruled by the army and the forces of corruption.
Â"I am painting a gloomy picture,Â" he said in his office in the presidential palace.
Wahid who is nearly blind after suffering two strokes in recent years has said his doctors had recommended that he travel abroad to seek medical treatment for his high blood pressure, which has been worsened by stress.
The vice presidential ballot came after much infighting between the country's political and military elites, who are jockeying for the top Cabinet posts in Megawati's new government in moves that are raising concern about Megawati's commitment to democratic reform.
Megawati is Indonesia's third president since the 1998 fall of former dictator Suharto, who ruled the country with an iron fist for 32 years. The country has had little success in consolidating democratic institutions in the three years since Suharto's demise.
Haz, 61, is the leader of the United Development Party and a former minister in Wahid's first Cabinet in October 1999. He resigned from the government the following month after allegations of corruption.
The balloting for vice president, which lasted 12 hours and was spread over two days, was marred by allegations of vote buying.
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