Abstract: Objective To study family clustering of chronic nasosinusitis among community residents in Guangzhou city,Guangdong province,for researches of genetic and environmental factors of the disease.Methods A total of 1 521 residents from 517 households in 8 communities in Guangzhou city were randomly selected with multi-stage stratified random sampling for a questionnaire survey.Chi-square goodness of fit test for beta binomial distribution and G statistic were use to test family aggregation of chronic nasosinusitis qualitatively and the degree of the family aggregation was evaluated with intra-class correlation coefficient.Results The prevalence of chronic nasosinusitis in the participants was 8.42%; no significant between-gender and between-age groups differences in the prevalence were observed,with a higher prevalence in the males than in females(9.10% vs.7.75%; χ²=0.736,P=0.3910) and the prevalences of 6.79%,10.13%,7.28%,and 9.27% among the participants aged ≤ 18,19-35,36-59,and ≥60 years(χ²=3.391,P=0.335).The prevalence of chronic nasosinusitis within the family showed a binomial distribution(χ²=3.717,P=0.054),with a total aggregation rates of 22.22%.The probability of chronic nasosinusitis in different families was not the same(T=5.222,P<0.001),with an intra-class kappa correlation coefficient of 0.094(Z=5.769,P<0.001).There were significant differences in chronic nasosinusitis prevalence among the families with different status of living conditions,keeping pets,using large carpet at home,type of fuel used,and dietary behaviors such as monthly consuming of fish/seafood,fruits and soy products(all P<0.05).Conclusion The family aggregation of chronic nasosinnusitis exists among community residents in Guangzhou city but the degree of the aggregation is weak and the aggregation is related to family environmental factors and dietary habits of the residents.