The role of modifiable risk factors in the development of dementia in Central and Eastern Europe remains understudied. We aimed to examine the association between 12 risk factors and the incidence of dementia in the Czech Republic and estimate the proportion of new dementia cases that can be attributed to these risk factors. Data of 3805 Czech participants in the Survey of Health, Ageing, and Retirement in Europe (mean age: 70 years, median 6.5-year follow-up) were analyzed. Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated using Cox hazard models for the association between the risk factors (low education, alcohol use, living alone, obesity, smoking, physical inactivity, high blood pressure, high cholesterol, diabetes mellitus, hearing loss, vision problem, and depression) and probable dementia diagnosis defined based on adapted Lang-Weir algorithm. We estimated the proportion of dementia cases attributable to each risk factor using weighted population attributable fractions (wPAFs). Four risk factors, low education (HR 1.72), depression (HR 1.42), diabetes mellitus (HR 1.53), and physical inactivity (HR 2.13), were significantly associated with dementia and accounted for the largest proportion of attributable risk. The total weighted PAF for all factors was 39.18%. If all risk factors for dementia were eliminated, almost 40% of dementia cases in the Czech Republic could be prevented. More systematic approach is essential for mitigating the adverse impact of risk factors on the incidence of dementia, such as improving education, preventing and treating depression and diabetes mellitus, and promoting physical.