According to the Forrester report, titled "Consumers barely trust Net advertising", online advertising ranks last behind newspapers, magazines, radio, TV and direct mail.
The report surveyed 10,000 adults and 8500 16-to-22 year olds online, of which only 14 per cent of adults, and 13 per cent of their younger counterparts trust online ads.
According to Ekaterina Walsh, the author of the report, both sets of consumers turn to the Internet for communication, entertainment, and research, not advertising.
The report found entertainment-motivated consumers trust more ads across all media, in contrast to high-income earners, who are the most skeptical target in the online demographic.
Technology "optimists" also have a positive attitude towards online advertising.
Users are least likely to trust ads in a chat room, and only 5 percent of 16-to-22-year-olds click on banners when chatting.
Advertisers looking for a better reception to their ads should sponsor non-profit sites and news sites which attract most respect from users, Walsh said.