A quarter of young people said they were picked on because of the way they look and 13% think they were targeted because of their weight.
The figures, revealed in a OnePoll survey, showed nearly 50% (49.6%) of children aged seven to 18 had been bullied.
Most of the abuse took place in schools and the top three places were in the playground, during break times and in the classroom.
Six out of 10 children said they had seen other people being bullied at their school and 80% of victims said it happened in front of other people.
Eight out of 10 had told someone about it and those who did not said they “didn’t think the person would be able to do anything about it”.
More than 70% of the 1,500 children surveyed knew their schools had an anti-bullying policy, but only a quarter thought it was working.
The survey was commissioned to launch Good Morning Britain’s Action! Against Bullying campaign, calling on schoolchildren to make a one minute anti-bullying film with the winner being shown in cinemas.
Good Morning Britain presenter Susanna Reid, described the findings as “shocking” and said: “We hope that the campaign will help raise more awareness around bullying particularly amongst schoolchildren.”
Former X Factor judge Louis Walsh who is backing the campaign, and was targeted at school, told the ITV show: “I wasn’t like everybody else, let’s put it like that, so I never thought I was going to fit in or do well in life but you always have people be negative, I want people to be positive”.
Find out more about Action! Against Bullying at itv.com.