Prabowo Subianto took the oath Sunday as Indonesia's eighth president, succeeding Joko Widodo who led the country for 10 years and vowing to be "leader of all Indonesians."
The inauguration ceremony was held in Jakarta with foreign dignitaries in attendance.
Prabowo, who served as defense minister in Jokowi's Cabinet, was elected in February after winning a landslide.
Following his inauguration, Prabowo, 73 proceeded to the presidential palace, where he was welcomed by the outgoing president.
In an emotional inaugural speech, the president vowed to be the "leader of all Indonesians," regardless of political differences, and to fight for the protection and welfare of the nation's most vulnerable groups.
The retired army general cited national unity and food security as the top priorities for his administration.
Promising that all of Indonesia's natural resources would be managed for the greater good of the masses, he vowed to continue the policies of his predecessor, including the industrialization of mining commodities and the ban on exporting raw minerals and ores.
"We will carry out this oath to the best of our ability and with accountability, prioritizing all the people, including those who did not vote for us," he said. His running mate, 37-year-old Gibran Rakabuming Raka, who is Jokowi's son, was also sworn in as vice president.
Turkish Defense Minister Yasar Guler also attended the inauguration ceremony and conveyed the best wishes of Turkish President Recep Tayyip Erdogan to Prabowo.