Haniyeh's tour will focus on raising investment and reconstruction funds for the war-torn coastal enclave, said Yusuf Rizqa, his political adviser.
It is the second foreign trip in two months for Haniyeh, who some believe is trying to raise his international profile as part of a power struggle with Hamas politburo chief Khaled Meshaal. Haniyeh recently visited Sudan, Turkey and Tunisia.
Meshaal has also been on the move, this week making his first visit to Jordan since 1999.
Haniyeh will stop in Iran at the official request of Iranian President Mahmoud Ahmadinejad, according to Taher Nono, a spokesman for the prime minister.
Iran has been a strategic supporter and donor for the Islamist militant movement, which has ruled Gaza since 2007. But Tehran reportedly cut back its funding of Hamas recently because Hamas has refused to express public support for Syrian President Bashar Assad, who is fighting to retain power amid a 10-month-old popular revolt in his country.
Though Haniyeh has remained in Gaza, other Hamas leaders, including Meshaal, have used Damascus as a base. But the recent unrest in Syria has caused most Hamas officials to leave the country.
Photo: Top Hamas official Ismail Haniyeh, center, returns to the Gaza Strip from a visit to Turkey and other nations in this Jan. 10 photo. Credit: Ali Ali / EPA