The uptake of smoking by children and factors influencing such behavior, although well documented in the West, have not been studied in the Asia-Pacific region. A cross-sectional survey was carried out on 3,521 children, aged 8-11 years living in two districts of Hong Kong. Knowledge, attitude and behavior related to smoking and sociodemographic data were obtained from questionnaires completed by parents and children. Eleven percent of boys and 5 percent of girls were ever-smokers, 5 percent of all eight-year-olds and 21 percent of 11-year-olds. Believing that parents will not interfere with their smoking (adjusted odds ratio 5.52; 95% confidence interval 2.72, 11.18), living with family members who smoke (1.72; 1.33, 2.23), and having a positive attitude to smoking (4.13; 1.43, 11.98) were factors predictive of ever-smokers. Experimentation with smoking is a major health risk for primary school children in Hong Kong and indicates failure of current smoking prevention programs. Effective culture-specific programs to counteract risk factors and with continuing evaluation are urgently needed; they should be based on information from appropriately-designed epidemiological studies.