Pain is one of the most frequent symptom in elderly people with dementia and despite of this, it is still under-acknowledged and under-treated. The best approach to pain assessment is to evaluate it with the most appropriate scale. While in the elderly suffering mild-moderate cognitive impairment, it's possible to use self-report scales, in the elderly with severe cognitive impairment the use of observational scales is recommended. The objective of this review is to analyze the various types of pain assessment tools used in patients with cognitive impairment. Literature review was carried out through consultation of the most important bio-medical databases: Medline (PubMed), KT+, Trip Database, Cinahl, Cochrane Library, Embase. The keywords used were: "pain measurement", "pain assessment", "dementia", "validation study", "aged". All keywords were linked using AND and OR boolean operators. Altogether 5 self-report scales and 17 observational scales were retrieved, 7 of which available in Italian validated versions. The review analyzes potential and limitations of each assessment tool, in order to assist the clinician to make the most appropriate choice when using it in health care contexts.