Objective: The aim of this study was to estimate the cost of dementia in the Czech Republic.; Methods: One hundred and nineteen patient-caregiver dyads participated in our multicenter observational cost-of-illness study. The modified Resource Utilization in Dementia Questionnaire was used as the main tool to collect data from patients and caregivers. Medical specialists provided additional data from medical records. The average costs of dementia were calculated and patients were then divided by the level of cognitive impairment. A generalized linear model was used to determine if differences were present for selected cost variables.; Results: The mean (standard deviation) for direct cost per a patient in a month was estimated to be €243.0 (138.0), €1727.1 (1075.6) for the indirect cost, and €1970.0 (1090.3) for the total cost of dementia in the Czech Republic. All of the costs increased as dementia severity increased. Both the indirect and total costs significantly (p < 0.05) increased if patients were living with their primary caregiver, and if the severity of cognitive impairment was increased.; Conclusions: The indirect cost, which was represented mainly by informal care, comprised the main part of the total cost of care for patients with dementia in the Czech Republic. Both total and indirect care costs increased significantly the cognition declined.