Antiquities director Maamoun Abdulkarim said much of Palmyra's old city was intact and his department would try to restore relics destroyed during the jihadists' nearly year-long rule over the city.
"We were expecting the worst. But the landscape, in general, is in good shape," he said.
"We could have completely lost Palmyra," said Abdulkarim.
"The joy I feel (today) is indescribable," he told AFP in a telephone interview from Damascus.
Since it overran the city in May 2015, IS destroyed the grand Temple of Bel, the shrine of Baal Shamin, and several funerary towers, which the ultraconservative Sunni Muslim extremists see as blasphemous.
The jihadists used the city's spectacular Roman theatre for executions and murdered the 82-year-old former antiquities chief of Palmyra.
Abdulkarim said the old ruins, located southwest of Palmyra's residential neighbourhoods, were in better condition than he expected.
Many of the most important ruins, including the Agora, Roman theatre, and city walls, were only lightly damaged, he said.
The limestone statue at the temple of Al-Lat, a pre-Islamic Arabian goddess, dates back to the 1st century BC.
Abdulkarim said the broken pieces "could be put back together - we didn't lose this great statue."
The citadel west of the city had suffered some of the most severe damage, with parts of it walls blown off by shelling.
"We will discuss with the United Nations how to restore the two temples (of Bel and Baal Shamin)," said Abdulkarim.
Abdelkarim said he would travel from Damascus to Palmyra soon to assess the damage.
