Polls opened at 6:00 am (0100 GMT) and were due to close at 8:00 pm (1500 GMT).
Over 16 million people were eligible to vote in Sunday's election.
Karimov, 69, was running against three virtual unknowns who have not once explicitly asked the ex-Soviet republic's 28 million people to vote for them in the election.
Europe's top vote monitoring body, the Organisation for Security and Cooperation in Europe, of which Uzbekistan is a member, is sending only 12 observers as it concluded that "the political process in Uzbekistan does not seem conducive to meaningful and effective competition."
On December 7 Karimov raised eyebrows in the diplomatic community with a bold pitch to foreign envoys in which he insisted he was pursuing a course "towards a free society and prosperous life."
Yet Karimov, who is accused by his exiled opponents of promoting torture and massacring hundreds in the city of Andijan in 2005, had also barely campaigned ahead of Sunday's polls.
A sprawling country of deserts, mountains and oases, Uzbekistan contains Samarkand, one of the world's oldest cities and resting place of legendary medieval conqueror Tamerlane.
But despite gas and cotton riches, Uzbekistan has failed to prosper since independence from the Soviet Union in 1991, something that critics blame on Karimov's uncompromising presidency.
He is famous for refusing to allow even flickers of opposition. In 2005 he launched a bloody crackdown on mainly unarmed protesters in the city of Andijan in which hundreds were killed, according to human rights activists.
The last time Karimov faced a political opponent at elections was 1991, the year of the Soviet collapse, when he was challenged by the poet-turned-politician Muhammad Solih, who later fled into exile.
The authorities have jailed numerous human rights activists and supporters of secular opposition groups, along with thousands of others convicted on Islamic extremism charges.
Between two and five million Uzbeks have left to work abroad, mostly in low-paying jobs, thanks to sluggish economic growth in this country that boasts large natural gas reserves and one of the world's largest cotton industries.
"The Uzbeks have already voted for liberty and prosperity by leaving," Surat Ikramov, one of the few remaining human rights activists allowed to operate, said.
"Society is completely paralysed. "
Güncelleme Tarihi: 23 Aralık 2007, 11:33