Lyme disease was suspected in 271 patients seeking hospital care between 1992 and 1996. The sera of all these patients were tested by ELISA for antibodies against Borrelia burgdorferi. Twenty-nine cases of Lyme disease were identified, each involving neurological and articular problems. These results demonstrate that Lyme disease occurs in Tunisia and suggest that this diagnosis should be considered more frequently in patients presenting with the characteristic symptoms.