Twenty eight percent of teenage girls have been victims of cyber-bullying, says GirlGuiding UK.
As a result of the research the group has put together advice on how young girls can deal with cyber-bullies.
Among other things, the association recommends victims don't ignore the problem, but tell others about the issue, keep social networking profiles on sites such as Facebook and MySpace private and resist putting their mobile number on their profiles.
Chief executive of Girlguiding UK Denise King said: "As the UK's largest organisation providing a safe female-only space for girls and young women, we see it as our responsibility to give girls and young women the knowledge and self-confidence to deal with issues that worry them".
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