Parkinson's UK said more than three-quarters (77%) of people have little or no knowledge of the degenerative neurological disease.
The charity said that, beyond the most visible sign of Parkinson's – a tremor or shake – most of those questioned (73%) did not know what other symptoms to look for, such as freezing to the spot or a fixed facial expression.
More than one in 10 (16%) of respondents said they would feel annoyed, embarrassed or uncomfortable if they encountered someone with a tremor.
Confusion surrounding how painful Parkinson's can be was also common, as 53% of people said they were unsure if the condition caused any pain at all.
Parkinson's UK published the research today to coincide with the launch of a new awareness campaign.
It will include advertisements featuring images of tasks that can be difficult for those with Parkinson's, including making a cup of tea and putting on shoes.
Steve Ford, the charity's chief executive, said: "These findings underline what we've been hearing from people with Parkinson's across the UK – that the general public simply don't understand their condition.
"Disturbingly, because Parkinson's is so poorly understood, those with the condition tell us all too often they are on the receiving end of these embarrassed and uncomfortable looks.
"We hope this new campaign will help to dispel some of the lingering fallacies surrounding the condition once and for all so that people with Parkinson's gain the understanding they so desperately need."