Depression is one of the most frequently diagnosed psychiatric disorders in patients with dementia with a prevalence of up to 50%. The detrimental effects of depression in dementia include disability in daily living, worse quality of life, and faster cognitive decline. Although electroconvulsive therapy (ECT) is a well-established and effective treatment for depression in the elderly, it is currently an overlooked treatment option in the elderly with dementia and depression. The aim of this review was to provide a critical analysis of the efficacy and safety of ECT in depression superimposed on dementia by reviewing the current literature on this topic. Current evidence suggests that ECT is an effective treatment for depression in dementia, although the relatively small number of controlled studies hampers the comparison of effectiveness between healthy nongeriatric patients and those with dementia. Moreover, the systematic reports on cognitive side effects are very limited in number and currently only apply to moderately mild or mild dementia of nonvascular origin. Some studies do suggest that cognitive side effects are likely in later stages of dementia and in patients with vascular dementia. It is therefore of crucial relevance to prospectively study effects of ECT in different types and phases of dementia in controlled trials. From a clinical perspective, it is essential to inform and educate patients and family about the possible risks and benefits of ECT treatment for depression in dementia.