Intensive care units are hostile places, which must be conditioned to the needs of patients and families, and therefore the factors that influence their satisfaction must be known. OBJECTIVE: To update the knowledge on the satisfaction of the patients admitted to an adult intensive care unit and that of their family caregivers as described in the scientific literature. METHODOLOGYy: A systematized literature review was carried out in PubMed, Scopus, Cinahl and WOS databases. SEARCH STRATEGY: "Personal Satisfaction" and (patients or caregivers) and "Intensive Care Units". INCLUSION CRITERIA: studies published between 2013-2018, population aged between 19-64 years, english and spanish language. RESULTS: 760 studies were located and 15 were selected. The factors that increased satisfaction are: good communication with professionals (n=5), the quality of care (n=4), and the cleanliness and environment of the units (n=2). The factors that produced dissatisfaction are: the infrastructure of the waiting room (n=5), inadequate communication (n=4), and the involvement of families and patients in decision-making (n=4). Training of professionals (n=5), inclusion of the family during the process of hospitalization (n=2) and redesigning the waiting room (n=2) are some of the suggestions for improvement. CONCLUSIONS: Factors related to professionals, environment and cleanliness of the units are satisfaction-generating factors. Factors generating dissatisfaction related to poor infrastructure, a lack of involvement in decision-making and poor professional communication. Strategies to improve patient and family satisfaction relate to the organization, professionals, family members, and infrastructure and environment.