BACKGROUND: The aim of this study was to identify factors associated with cancer screening practices and with general attitudes toward cancer screening in a general population. METHODS: Mailed survey of 30-60 year old residents of Geneva, Switzerland, that included questions about screening for five cancers (breast, cervix uteri, prostate, colon, skin) in the past 3 years, attitudes toward screening, health care use, preventive behaviours and socio-demographic characteristics. Cancer screening practice was dichotomised as having done at least one screening test in the past 3 years versus none. RESULTS: The survey response rate was 49.3% (2301/4670). More women than men had had at least one cancer screening test in the past 3 years (83.2% vs 34.5%, p < 0.001). A majority of women had had a cervical smear (76.6%) and a mammography (age 30-49: 35.0%; age 50 and older: 90.3%); and 55.1% of men 50-60 years old had been screened for prostate cancer. Other factors associated with screening included older age, higher income, a doctor visit in the past 6 months, reporting a greater number of preventive behaviours and a positive attitude toward screening. Factors linked with positive attitudes included female gender, higher level of education, gainful employment, higher income, a doctor visit in the past 6 months and a personal history of cancer. CONCLUSION: Attitudes play an important role in cancer screening practices among middle-aged adults in the general population, independent of demographic variables (age and sex) that determine in part screening recommendations. Negative attitudes were the most frequent among men and the most socio-economically disadvantaged. The moderate participation rate raises the possibility of selection bias.