President Halimah Yacob has written to Iranian President Hassan Rouhani to convey her condolences following the plane crash in central Iran.
Aseman Airlines flight EP3704 was carrying 66 people when it disappeared from the radar as it flew over the Zagros range on Sunday morning, around 45 minutes after taking off from Teheran.
President Halimah told Mr Rouhani that she was "saddened to learn about the tragic crash".
"On behalf of the people of Singapore, I extend our deepest condolences to Your Excellency, the families of the victims, and the people of the Islamic Republic of Iran. Our thoughts and prayers are with the bereaved during this difficult period," she wrote, according to a statement from the Ministry of Foreign Affairs.
Iranian search teams found the plane wreckage yesterday, reported Agence France-Presse.
After two days of heavy snow and fog, the weather finally cleared, giving helicopter teams better visibility.
"The Revolutionary Guards' helicopters this morning found the wreckage of the plane on Dena mountain," spokesman Ramezan Sharif told state broadcaster IRIB.
A pilot told IRIB he had seen "scattered bodies around the plane" and that it was located in Noghol village. But the steep terrain made it impossible to land and officials warned there was only a small window of time before bad weather returned.
The ATR-72 twin-engine plane, in service since 1993, flew early on Sunday from the capital's Mehrabad airport towards the city of Yasuj, some 500km to the south.
The incident has reawakened concerns over aviation safety in Iran, which has been exacerbated by international sanctions over the years. Aseman Airlines was blacklisted by the European Commission in December 2016.
Iran has complained that sanctions imposed by the United States have made it difficult to maintain and modernise ageing fleets.