Elections were to take place next year, but Nazarbayev changed the date in February, explaining the move as a requirement to avoid political instability amid a global economic crisis.
There are three candidates for presidency, including the current president Nursultan Nazarbayev, 75, who has been the Kazakh leader since the fall of the Soviet Union in 1991. He was reelected to his fourth consecutive term in April 2011.
Under the Kazakhstan constitution, a candidate cannot be elected president more than twice in a row, but Nazarbayev has been exempted from this restriction by a constitutional amendment in May 2007.
Two other candidates are Kazakhstan's Communist Party functionary Turgun Syzdykov and a former regional governor, chairman of the Federation of Trade Unions Abelgazi Kusainov.
More than 800 observers from 19 countries at the polling stations reported no significant violations during the voting.
Kazakhstan's Foreign Ministry accredited 168 representatives of foreign mass media from 37 countries.
