Rare diseases are a serious public health problem and are a threat to the health of EU citizens. Important role in the area of rare diseases have the medical specialists who diagnose and monitor the course of the disease of each patient. General practitioners (GPs) are usually the first to identify "unusual" patients that might have a rare disease. The GPs awareness and knowledge about rare diseases is a strong factor for the timely and accurate diagnosis and adequate treatment of rare diseases conditions. A telephone interview was conducted among the GPs in Bulgaria between January and March 2008. A set of 10 questions with pre-defined answers was constructed and offered to the GPs in order to determine their level of knowledge and awareness of rare diseases. Data were statistically processed using specialized software SPSS version 9.0 (SPSS, Inc., Chicago IL). The responses of surveyed doctor indicate a low level of general knowledge and awareness. This means, that GPs from the primary health care system in Bulgaria could not provide sufficient in quality and timeliness specific information to their patients with rare diseases. A campaign for increasing the awareness of GPs about rare diseases is needed.