The findings of the ICM survey, conducted for the Jewish Chronicle newspaper, showed that 15% of those polled agreed the scale of the Holocaust has been exaggerated.
Seventy percent disagreed with the statement, and 62% disagreed with it strongly, according to the survey, which was published in the left-wing Guardian daily newspaper.
Historians put the number of Jews killed during the Holocaust at around six million - a statistic compiled from post-World War II census numbers.
Moreover, nearly 20% of those questioned in the poll - timed to coincide with Holocaust Memorial Day next Tuesday - said that a Jewish prime minister would be less acceptable than a member of any other faith.
Asked whether a British Jew would make an equally acceptable prime minister as a member of any other faith, 53% agreed and 18% disagreed, 11% strongly.
Michael Howard, head of the opposition Conservatives, is the first Jewish leader of a major political party in recent times in Britain.
Conservative leader Michael
Howard is Jewish
The poll of 1007 people in England, Scotland and Wales found 37% agreeing that Jewish people make a positive contribution to political, social and cultural life of Britain, with 20% disagreeing.
Meanwhile, 18% agreed that Jews had too much influence, while 47% disagreed.
Britain's Home Secretary David Blunkett, interviewed by the Guardian, expressed his disappointment at the poll's findings.
"It means people are prepared to set aside not only the evidence, but the overwhelming emotion that goes with it," Blunkett said.
"They delude themselves into believing that the Nazis are not what we know them to be and this is very depressing."