Background Timely diagnosis involves making and sharing a diagnosis at a time and in a way that are most appropriate for the physical, emotional, medical and other needs of the patient and their family. GPs are often the first point of contact for people who are concerned that they may have dementia and, therefore, have an essential role in the timely diagnosis and disclosure of this condition.Aim To explore the views of GPs in relation to the timely diagnosis and disclosure of dementia for patients and their families in primary care.Method This was a small-scale qualitative study in which a survey questionnaire was sent to GPs practising in one health service executive locality in the west of Ireland. A total of ten GPs completed the questionnaire, and descriptive content analysis was used to explore their responses.Findings Enablers of timely diagnosis and disclosure of dementia included: patient and family awareness of dementia; access to diagnostic resources and multidisciplinary assessments; having sufficient time to disclose the diagnosis sensitively; and the availability of community-based, dementia-specific support. Barriers to timely diagnosis and disclosure of dementia included: diagnostic uncertainty; concerns about misdiagnosing patients; and concerns about the stigma associated with dementia and how patients and their families might react to disclosure of such a diagnosis. There was widespread agreement among the GPs that timely diagnosis and disclosure benefit patients and their families, but also some scepticism regarding the efficacy of diagnosis and treatment for dementia (therapeutic nihilism).Conclusion The diagnosis and disclosure of dementia in primary care could be enhanced by improving GPs’ access to resources such as multidisciplinary assessments, memory clinics and community-based support schemes. Primary care and community mental health nurses have an important role in providing expertise to GPs and support to patients and their families.