A survey found the most common age for first trying cannabis is 15
Nearly one in 10 children in Northern Ireland under the age of 12 have tried cannabis, according to a new survey conducted by Queen's University.
The survey also found that young people in Northern Ireland are more likely to experiment with drugs than their peers in the rest of the UK and Europe.
Figures suggest that 45% of teenagers aged 18 and under have tried cannabis.
The Youth Development Survey questioned 4,000 pupils about drugs in 43 schools in Belfast, Ballymena and Downpatrick.
The findings will be discussed by teachers, health educationalists and drug prevention professionals at an event in Queen's on Monday.
Dr Patrick McCrystal, a senior research fellow at the university's Institute for Child Care Research, said the results highlighted the need to educate young people about the risks of experimenting with drugs.
He said a number of teenagers who took part in the survey appeared to have "developed a drug-using lifestyle by the age of 16".
Dr McCrystal added that the findings relating to cannabis were important because it is "often considered the 'gateway' drug to more serious substance abuse".
"In nearly all cases, cannabis is the first illegal drug used by young people - and almost all of those who reported using cocaine or ecstacy also used cannabis.
"Levels of cannabis use by these young people is higher than among teenagers of the same age in the UK, Ireland and Europe.
"Of the young people who had tried cannabis, around one in ten went on to use it on a weekly basis by the age of 16," he said.
Later this week, researchers from across Europe will gather at Queen's to discuss drugs-related issues when the university hosts the 20th annual conference of the European Society for Social Drug Research.