More than 90% of males here have no idea what the prostate does despite one man in the UK dying every hour from cancer of the gland.
A poll of more than 3,500 people, 513 of them from Northern Ireland, by Prostate Cancer UK exposes widespread ignorance.
It reveals that 53% of men here don't know where it is in their body, only 9% know what it does, and 15% are unaware that they even have a prostate.
It comes as Prostate Cancer UK launches a campaign urging men to stop ignoring the disease.
The charity has voiced concern that poor awareness of the gland, which is key to sexual function, may blind men to their risk of prostate cancer and prevent them from taking action to tackle the disease.
Almost 8,500 men here are living with prostate cancer, with three new cases diagnosed every day. Around 250 die each year.
Prostate cancer is the most common male cancer, followed by colorectal and lung. Angela Culhane of Prostate Cancer UK said: "Ignoring your prostate can be lethal. You can't see it, you can't feel it, and shockingly many men only realise they have a prostate when it starts to go wrong."
The prostate is the size and shape of a walnut and grows bigger as men age. It sits under the bladder and surrounds the urethra.
The poll also shows that 88% of men across the UK at higher risk of prostate cancer are unaware of their increased danger, with 11% of these believing they are actually at lower risk.
The charity warns that if the rising death trend is allowed to continue, by 2026 the disease will claim 14,500-plus lives every year, 3,600 more than today.
However, the charity says that with the right action from clinicians, researchers and funders, projected deaths from prostate cancer can actually be halved by 2026, with better diagnosis and treatments making it a disease the next generation needn't fear.
Ms Culhane added: "If men really knew what the prostate can do to them they wouldn't ignore it. As a country, we need to wake up and stop men dying needlessly. Ignoring prostate cancer won't beat it - only fighting it will. Now is the time to join the fight to beat this disease.
"Prostate cancer won't beat itself. It's a race against time but we believe it can be tamed within 10 years if action is taken now. However, 'out of sight, out of mind' can be a death sentence. Every man should wise up to prostate cancer so that it doesn't end up killing him."