"We hope that upcoming years will be a great opportunity for Syria to return to playing its natural and leading role globally and regionally," it said.
Iran's President Hassan Rouhani also congratulated Syria's Bashar al-Assad, according to an Iranian presidential website.
"I sincerely congratulate you on the successful conduct of the elections and your re-election as President of the Syrian Arab Republic," Rouhani said in a statement to Iran's close ally Assad.
"The Syrian people took an important step in deciding the fate and prosperity of Syria with their large turnout and decisive choice," Rouhani added, according to his website.
Assad won the election on Thursday with a majority of 95.1%.