We have performed a total of 107 cultures from three critical areas of an Olympus Panendoscope Model GIF-D2 in order to evaluate bacteriologically cur system of desinfection of this endoscope. Samples were taken from the distal end, external surface and biopsy canal before and after an endoscopic examination was performed. The procedure of desinfection employed was as follows: washing of the distal end, external surface and biopsy canal with Hexaclorophel (Phisohex) diluted 50% with water and a second washing with tap water. In the middle of the study, we added a second washing of the biopsy canal with ten ml. of ether alcohol to allow for better drying. As a result of the present study we observed that in the distal end in 50% of the samples we encountered bacteria. Cultures of the external surface were positive in 20% of samples. The biopsy canal should be washed with ether alcohol to allow for complete drying, because when we did not use this method, Pseudomonas Aeruginosa was isolated. After this modification we did not isolate bacteria. The most frequent types of isolated bacteria were from the normal oropharyngeal flora. From the present study we can conclude that desinfection of the Panendespe with Hexaclorophen gives satisfactory results on the external surface of the endoscope. Biopsy canal requires additional washing with ether alcohol. However, both procedures do not assure a satisfactory desinfection of the distal end.