Clinical observation was carried out for 147 patients with mucocutaneous lymph node syndrome (MCLS) who were admitted to the Department of Pediatrics, Wonju Christian Hospital during the period from June, 1983 to June, 1992. A spinal tap was performed on 114 of these patients and the following results were obtained. 1) The incidence of aseptic meningitis in patients with MCLS was 52.6%. (60 cases of the 114 cases who had spinal taps (52.6%).) 2) The predominent age group for aseptic meningitis was 6 months to 1 year of age (35%). 3) For the majority, the value of glucose and protein in the CSF were within normal limit or only mildly elevated. 4) The neurologic manifestations associated with aseptic meningitis in patients with MCLS were irritability (78.3%), vomiting (25.0%), nuchal rigidity (11.7%), convulsion (5.0%) and facial nerve palsy (1.7%) in that order.