Abstract: The study aimed at analysing the epidemiology, demographic and clinical aspects of Acinetobacter species in Aseer Central Hospital, Abha, Aseer region South-West Saudi Arabia. This study was conducted from December 2011 to June 2012 at Aseer Central Hospital. One hundred fifty patients were identified. Demographic, epidemiological and clinical data were collected using a special questionnaire. The isolates were identified using bacteriological tests; direct microscopy, culture in blood agar media, fermentation test in MacConkey media and Chemical test using API 20. Significant risk factors were working age (16-60 years), 58.7% males and 41.3% females. The 97% of the patients were Saudi; one-third of those were unemployed, 18% employed worked in military and only 3.3% worked as health personnel. Sputum (47.3%), blood (22.7%), skin (14%), urine (6%) and fewer samples were eye swap, endotracheal tube and wound swap samples were collected. The 41.3% of patients were from the medical word and 22.7% were from the Intensive Care Unit (ICU). The average of inpatients hospital day stay was around 4 days. Acinetobacter bacteria are the important cause of the nosocomial infections. The risk factors for Acinetobacter species infections involved the improper and irrational use of broad-spectrum antimicrobials and invasive procedures.