Behcet's disease is a progressive and/or relapsing-remitting multisystem inflammatory disorder. Involvement of the central nervous system occurs in 10%-29% of cases with Behcet's disease. The aim of the present study was to assess the effect of repetitive auditory stimulations on event-related potentials (ERP) in patients with Behcet's without neurologic manifestations. The study was performed in 14 patients with Behcet's disease and 14 healthy volunteers. ERPs were recorded from Fz, Cz and Pz. The auditory ERPs test was continued until 20 artefact-free rare tones were averaged, which was accepted as one trial block. After six blocks were obtained in a sequential manner, the test was completed. According to the results of the present study, P300 latency changed in different manners over trial blocks in the two groups. P300 latency values showed a progressive increase in the controls; however this was not determined in the Behcet's group. Thus, habituation was not observed in the patient group. Because of the lack of habituation related to P300 latency, it may be thought that there is an insidious pathologic process in Behcet's disease without neurologic manifestation.