Irans President Hassan Rohani is due to take the oath of office, following his endorsement by Leader of the Islamic Revolution Ayatollah Seyyed Ali Khamenei.
The inauguration ceremony will begin in Irans capital, Tehran, on Sunday in the Majlis building.
Ayatollah Ali Khamenei officially endorsed Rohani for a four-year term in office as Irans new president in a ceremony on Saturday.
Delegations from more than 50 countries will attend Rohanis inauguration ceremony at Majlis. Among the participating foreign dignitaries are ten presidents, six vice-presidents, two prime ministers, eight parliament speakers as well as several prominent former officials.
Former European Union foreign policy chief Javier Solana and former Malaysian Prime Minister Mahathir Mohamad will also take part in the ceremony as special guests.
UN Deputy Secretary-General Jan Kubish will participate in the event as the representative of UN Secretary-General Ban Ki-moon.
Iranian Foreign Ministry Spokesman Abbas Araqchi said in July that leaders and officials from across the world, except for the United States and Israel, have been invited to Rohanis inauguration.
Rohani won Irans June 14 presidential election with 50.7 percent of a total of 36, 704, 156 ballots. The voter turnout in the election was 72.7 percent.