To find the prevalence of burnout syndrome in general practitioners of the Public Sanitary Service in a health area in Zaragoza (Spain) and compare the results with the original American and two Spanish samples (general practitioners and specialists). A descriptive, crossover population study. General practitioners of the Public Sanitary Service in a health area in Zaragoza (Spain). A sample of 286 general practitioners was selected through random conglomerate sampling in 37 health centres (14 rural and 23 urban). We used an anonymous self-administered enquiry method. It included Maslasch Burnout Inventory (MBI), which values the three syndrome dimensions: emotional exhaustion (EE), depersonalization (DP) and lack of personal accomplishment (PA), and two own questionnaires related to the job and personal beliefs. 144 people (63 female and 81 male) between 29 and 69 years old were studied. 59.7% showed high levels of burnout on EE subscale, 36.1% on DP subscale and 31.2% on PA one. Comparing with the original American sample, we obtained significantly differences on EE and DP subscales whereas comparing with the Spanish general practitioners one we obtained significantly differences on EE and PA. Comparing with the Spanish specialists one we obtained significantly differences on DP and LP. There's a serious prevalence of burnout syndrome in general practitioners, particularly on EE subscale. There should be quick interventions in health policy in order to control and prevent this issue.