Fifth of children are cyber-bully victims
Many victims said the experience had damaged their confidence, mental health and even school attendance.
The study, by academics at Anglia Ruskin University, questioned almost 500 young people aged between 11 and 19.
Almost a fifth (18.4%) admitted they had been subjected to cyber-bullying, in which a person uses the internet or mobile phones to bully another.
Of the 273 girls questioned, 60 (22%) said they had been subjected to cyber-bullying, while out of the 200 boys quizzed 27 (13.5%) said they had faced it.
And two thirds (66%) of the young people questioned (312 people) said they had witnessed cyber-bullying or known someone who has been a victim.
The 87 youngsters who had experienced cyber-bullying as victims were asked what impact this had had on them.
A third said it had affected their confidence ''quite a lot'' or ''very'' much, while half (52%) said cyber-bullying had affected their mental and emotional wellbeing.
Just over a quarter (29%) of those who had been cyber-bullied had stayed away from school, while more than a third (39%) had stopped socialising outside of school.
Of those 188 young people who answered a question about whether they would seek help with cyber-bullying, less than half (45%) said they would look for support.
Those that said they would not seek help gave fear of making it worse and being able to deal with it themselves as some of the reasons.
The youngsters who had been cyber-bullied were most likely to seek help from parents and friends, the research found.
Steven Walker, who led the research said: ''While most online interactions are neutral or positive the internet provides a new means through which children and young people are bullied.''
He added: ''Many of the respondents in our study thought that cyber-bullies do not actually think they are bullying. In the main they thought that cyber-bullying was seen by bullies as merely a form of 'harmless fun', a joke and therefore not an issue.
''Others thought cyber-bullies are motivated by a lack of confidence and a desire for control, perhaps because they are too cowardly to bully face-to-face.
''As the use of social media amongst young people continues to grow, unless properly addressed by host sites and Government agencies the problem of cyber-bullying is only likely to get worse.''