Knowledge about the prevalence of nursing diagnosis (ND) helps to provide the necessary care and to guide continuing education programs. This cross-sectional study aimed to identify the main nursing diagnosis (ND) prescribed in intensive care units (ICU) and to compare them with medical and surgical patients. Data analysis was performed according to the North American Nursing Diagnoses Association (NANDA) Taxonomy II. In the 150 medical records evaluated were found 195 nursing diagnoses, with an average of 1.3 per patient, mainly in the protection and security domain (39.5%). The most common ND were: impaired tissue integrity (22%), impaired gas exchange (22%), ineffective cerebral tissue perfusion (8.7%), impaired skin integrity (7.7%), decreased cardiac output (6.7%) and ineffective tissue perfusion cardiopulmonary (6.1%). The most prevalent nursing diagnoses revealed the physiological needs as the most common in our sample.