More than 30 per cent of students surveyed recently said they were addicted to the internet and felt anxious and irritable when they were stopped from logging on.
The Hong Kong Federation of Youth Groups' social workers interviewed 1,508 secondary students from 31 schools in November and December.
About a third of the respondents - 266 male and 208 female - said that they were addicted to the internet in that year. Other addictions afflicting students included drinking (26 per cent), gambling (12 per cent) and smoking (4 per cent).
Reasons cited for their addictions included 'killing time', 'deriving pleasure from the behaviour', and 'lessening unhappiness'.
Ah Sit, a Form Four student, said he had been addicted to Facebook and online video games for four years.
'My academic performance suffered because of my addiction,' he said. 'I had to repeat Form Four studies this year. The addiction also alienated me from my family. Arguments frequently break out between us when they switch off the computer or unplug the modem to stop me playing games.'
Ah Sit has had counselling from a federation social worker at his school for three years.
Survey organisers said student addicts were reluctant to seek help for their obsession, with 35 per cent of respondents saying they would not take the initiative to get assistance.
Reasons cited for their reluctance included 'unwillingness to let others know about their addiction' and 'confidence in being able to tackle the addiction on their own'.
Federation supervisor Angela Ngau Mei-mui said students overestimated their ability to exercise restraint and were not motivated to seek help.
'It's easy for them to fall into addiction unwittingly,' she said.
Hsu Siu-man, supervisor of the federation's Youth Wellness Centre, which was set up two months ago to help young people kick their addictions, said the centre had received 85 cases over the past two months.
'Around 80 per cent of the cases are related to online addiction, with other cases involving addiction to alcohol and drugs,' she said.
She appealed to young addicts to take the first step to get help. 'Once they have developed a psychological and physical dependence on this behaviour, it's difficult to quit,' she said. 'Addicts pay a big price for their obsessive behaviour, like poor health, unemployment, poor studies and poor relationships.'
A youth centre was set up recently to help fight various addictions
Out of 85 cases in two months, the proportion of online addicts was: 80%