85 cases of neurosyphilis were observed in Seoul National University Hospital over 6-year period (1979-1984). They were analyzed with respect to clinical symptoms and signs in individual types, serological data in both blood and CSF, changes of cytochemical compositions in CSF, and other significant findings. And some coparisons with other reports were made. They ranged from 22 to 66 years in age with the peak incidence in the forties (41%). Ratio of male to female was observed to be 4.3:1. There were 27 cases of asymptomatic neurosyphilis (NS) (32%), 14 cases of tabes dorsalis (16%), 18 cases of general paresis (21%), 2 cases of taboparesis (2%), 7cases of vascular NS (8%), 6 cases of meningeal NS (7%), 4 cases of syphilitic eight nerve involvement (5%), 4 cases of late syphilitic ocular involvement including optic atrophy (5%), and 3 cases of spinal form (4%). Except in 4 self-referral cases, alimentary system symptoms or illnesses were the main prolbems in asymptomatic neurosyphilitics (48%). Most symptomatic cases had the similar clinical pictures as described in the previous reports but some cases appeared to be combined with symptoms and signs of different types. In tabes dorsalis, patients presented paresthesia and hypoactive DTRs in lower limbs as the most frequent features. According to predominant manifestations, there were 4 cases of dementic form and 14 cases of psychotic form in general paresis but in most cases both features overlapped each other. In 8 cases of general paresis brain CT scans were performed, which revealed diffuse cerebral atrophy in five. Focal abnormalities of vascular NS were most frequently found in temporal areas (4 in 7 cases). Meningeal irritation signs were observed only in one among 6 cases 6 meningeal NS. All cases of eighth nerve involvement showed sensorineural hearing loss at high-tone level. Compared with TPHA, which was used as a criterion for the patient selection, VDRL reactivity was 98% in serum and 49% in CSF. It is notable that as for general paresis and meningeal NS, higher reactivity and elevated titers of CSF VDRL were associated with increase of cells and total protein in CSF, suggesting higher disease activity in both types. Unlike those from other countries, the domestic studies including this report show that general paresis occupies a relatively higher proportion than tabes dorsalis in Korea.