The UN children's Fund (Unicef) says its two-year campaign with the Sri Lankan tourist board against child sex tourism is being intensified.
Poorer children are especially at risk
Unicef officials say that the campaign will now be extended to include TV, radio and newspaper announcements.
Messages have been relayed to tourists through in-flight magazines and videos since the two-year campaign against child sex tourism began last month.
Those guilty of sexually abusing children face up to 20 years in jail.
"As the campaign has got under way, we have also begun raising awareness of the problem among three-wheeler taxi drivers," Mihiri Fernando, spokeswoman for Unicef's Combating Child Sex Tourism project, told BBC News.
"We have also started a hotline for children or any member of the public to call in and report cases of child sex tourism.
"We have also got agreement that the next set of embarkation cards for tourists entering the country will carry the 'Zero tolerance for child sex tourism' message.
"The mass media campaign will begin next week," she said.
Some tourists do not come only to see Sri Lanka's beauty
Unicef says that Sri Lanka is the first country in South Asia with a national plan of action to combat child sex tourism, and now has "a unique opportunity" to lead the way for other countries in the region.
It says that while the exact numbers of child sex victims are not known, it is estimated that thousands of children are drawn into prostitution in Sri Lanka every year.
The majority of those are boys who are offered money, clothes, pens, sweets, food and sometimes the chance to travel overseas as enticements.
Unicef say that the children are exploited by foreign tourists as well as by local people.
The most vulnerable are those from poor and marginalised communities who have little supervision from their families.
Figures show that last year 549,000 foreign tourists visited Sri Lanka, with the number projected to rise to 600,000 in 2006, and up to one million by 2010.
The International Labour Organisation estimates that nearly two million children globally are exploited in the multi-billion dollar commercial sex industry.