Missed nursing care is a subset of the category known as error of omission. It means that the needed nursing care that is delayed, partially done, or not finished at all. Missed nursing care is a matter of concern because nurses coordinate, provide, and evaluate many interventions as a part of health team towards treatment ofpatient illness. Moreover, a nurse also plans, implement, and evaluate nurse-directed care to manage patient’sclinical manifestations and responses to care, and to promote health and healing. Thus missed nursing care is not only a type of Medical error that may affect safety and prognosis, but has contributed to be a unique type of Medical underuse. Keywords: Missed nursing care, Patient prognosis, Donabedian’s structure process outcome.