Several studies have indicated a poor nutritional knowledge among physicians, thus a survey was carried out to determine the nutritional knowledge of physicians working in general and private practice (governmental and non-governmental centers, respectively) in Iran. Data were collected by means of a questionnaire including multiple-choice questions. The study was conducted among randomly selected 200 physicians (male: 140, female: 60) working in clinics related to the Ministry of Health and Medical Education (MOHME). The responses of the physicians to the questions about nutrition (particularly hypertension, diabetes and obesity) were evaluated by scoring them. The average scores of the nutrition knowledge level of the male and female physicians were 9.61 +/- 2.63 and 9.61 +/- 2.85, respectively. It was found that the nutrition knowledge level of just 13.1% of the physicians was mediocre and 86.9% was poor. The results indicate that physicians don't have enough knowledge about important topics in nutrition such as diet therapy in topics mentioned; therefore they need more education in nutrition.