Their chief concerns are being judged on how they look and being bullied.
The report, Teenage Mental Health: What Helps and What Hurts? found that bullying was raised by teenagers at every consultation venue.
A total of 277 teens took part in the consultations last October in Athlone, Cork, Dublin, Limerick and Sligo organised by the Office of the Minister for Children and Youth Affairs.
Danny Costello, one of the teenagers who attended one of the Dublin consultations, said bullying went on 24/7 in different ways.
He admitted being bullied for many years both in and out of school, but school was where the most bullying would take place.
And the other places where bullying occurred all had to do with school.
“Take Bebo for a start. You will find all your classmates, friends, peers and then the ones you do not want to find will find you,” he said.
“But, whether you block them or not, the bullying will not stop,” he said.
Danny also warned emotionally stressed teens might also suffer from depression.
“Depression makes youths feel there is no way out, no one there for them and with a constant amount of bullying in their ear, this could not be good for anyone.”
The question of homophobic bullying was also raised at the launch of the report by the Minister for Children, Barry Andrews, who said it was widespread and must be tackled.
He found it particularly worrying some young people had experienced homophobic bullying by teachers.
Mr Andrews said young gay people had told of their experience of homophobic bullying that was very significant, very damaging and very traumatising.
The use of new technology in bullying, including social network sites and text messaging, meant the perpetrators did not see the consequences of their actions.
When asked what hurt mental health the most teenagers outlined eight key areas: self image; school pressure and exams; family problems; bullying, death; peer pressure, relationships and isolation.
Mr Andrews said the exam system and the school environment were priority issues that needed to be addressed.
Minister for Disability and Mental Health John Moloney said the National Office for Suicide Prevention was leading a campaign aimed at teenagers to raise awareness of mental health issues.