OBJECTIVES: The purpose of this study is to describe health service use and related costs associated with potentially inappropriate prescriptions (PIP) of benzodiazepines (BZD) in the elderly living in the community in the province of Quebec, Canada. METHODS: The cohort consisted of a representative sample (n=2494) of Quebec’s community-dwelling elderly (>65 years of age) respondents of the ESA survey (Survey on older adult’s mental health, 2006). The cost analysis was carried out from a healthcare system perspective and the definition of the PIP of benzodiazepines was based on Beers’ criteria (Fick, 2003). Multivariate regression analyses were carried out to assess the influence of PIP of BZD on healthcare costs in the elderly. RESULTS: 30% (n=744) of participants were using BZD and 45% (n=331) of the users received at least one PIP. Higher healthcare costs (14196$ vs. 9992$; p<0.0001) were observed for participants with the presence of PIP of BZD in comparison with those without PIP.  When individual and health care system factors were controlled, health care costs were still higher for BZD users with PIP without being statistically significant at a 95% level (β (log($)) = 0.109; IC95: [-0.040, 0.259]; Δ $ : 1180$). Factors associated with higher healthcare costs were gender and physical health status. CONCLUSIONS: Using both administrative and survey data, this study provides new data that will help decision makers better understand the economic impact associated with the inappropriate prescriptions of BZD. The significant association between the PIP of BZD and the healthcare costs observed in the univariate analysis seems to be mainly explained by the patient’s physical health status. Nonetheless, with the current economic and clinical context, particular attention should be given to the inappropriate prescriptions of BZD, affecting 45% of users and 14% of the senior population in Québec.