More than 1.3 million Mongolians go to the polls on Sunday to choose a new president from four candidates.
Voters are seen lining up at several polling stations in the capital Ulan Bator and the voting is reported to be orderly.
Some 1,631 polling stations are open between 7 a.m. and 10 p.m.(2300 GMT Saturday and 1400 GMT Sunday). Ballot counting will begin immediately after the polling stations are closed.
Mongolia's General Election Committee said the election is under the watch of around 100 international observers from Britain, Japan, the United States and some other countries.
Three independent opinion polls suggest that among the four candidates, Nambaryn Enkhbayar of the Mongolian People's Revolutionary Party is likely to win an outright victory. He now serves as chairman of the Great Hural, the parliament.
Under Mongolia's electoral law, a run-off is to be held on June 5 if no candidate gets more than 50 percent of the vote.
The Democratic Party's Mendsaikhan Enkhsaikhan, who is chairman of the Great Hural's standing committee of security and diplomacy, was in a distant second place in the opinion polls with support of about 26 percent.
Source: Xinhua