The term mild cognitive impairment (MCI) aims to represent an intermediate stage between normal aging and the development of pathologic aging and dementia. The etiology is heterogeneous divided in amnestic or non-amnestic causes. Most of the patients in amnestic causes after several years progress to Alzheimer disease. For the diagnosis, there are biomarkers and screening which help. The individuals aged 65 and older in the United States and worldwide are growing in number; the implications of the effect of multimorbidity on risk of age-related conditions such as mild cognitive impairment (MCI) and dementia are highly relevant for public health planning, allocation of resources, and development of strategies to reduce risk of these conditions.MCI is a term used to describe cognitive impairment in one or more cognitive domains that is greater than any expected age-related changes but is not a diagnosis of dementia. Until now no established treatment exists for mild cognitive impairment (MCI). Cholinesterase inhibitors have not been found to delay the onset of Alzheimer disease (AD) or dementia in individuals with MCI. Present review is based on scientific evidence and information about the mild cognitive impairment. It is focused on the etiology, epidemiology, diagnosis, declining cognitive measure, differential diagnosis, prevention and possible treatments.