Introduction: Measuring patient satisfaction with health services in recent decades has been an important tool for assessing the quality of specific services. Purpose: The investigation of the degree of satisfaction of patients attending the Regular Outpatient Clinics of a General Hospital as well as the effect of socio-demographic factors on their satisfaction. Method: For the gathering of research data, a structured questionnaire with "closed" questions was used regarding the patients' satisfaction with the reception - environment, speed of service, clinical and laboratory examinations, impressions from the medical care, impressions from the nursing care, the administrative services and the general service. Results: The study involved 36 men (57.1%) and 27 women (42.9%) with a mean age of 56.78 years. The majority of them were insured (79.4%), Greek citizens (90.5%) and high school graduates (36.5%). Also, most outpatients evaluated very satisfactorily the services provided by the Regular Outpatient Clinics of the Hospital. Finally, there was a statistically significant correlation between socio-demographic variables (age, insurance and nationality) and patient satisfaction level (p <0.05).Conclusions: Based on the findings of this research, there is a clear effect of socio-demographic factors on the degree of satisfaction of outpatients.