The annual Health Survey for England found that although 92% of men and 89% of women had heard of units of alcohol, 35% of men and 43% of women did not know the recommendations for their sex.
Those who attempted to define the recommendations were more likely to be wrong than right, the poll added.
Drinkers aged 25-54 were more likely to know the recommendations than those of other ages.
The poll found that 90% of men and 84% of women drank alcohol, with the majority having drunk alcohol in the past week and 22% of men and 13% of women having drunk alcohol on five or more days in the past week.
Among those who had drunk in the past week, the majority drank more than government recommendations on at least one day, with 35% of men and 27% of women drinking more than twice the recommended levels on at least one day.
Most British adults believed that drinking was a major part of the British way of life – although many also believed that people in other parts of Europe tended to drink more sensibly than Brits.
A minority of those polled thought the government should hike alcohol duty to encourage people to drink less.