Congenital deficiencies of complement system proteins are rare. A 4-year-old girl was admitted for meningitis. She had had repeated attacks of pneumococcal meningitis and otitis media at the age of 3 years. Analysis of cerebrospinal fluid showed that this meningitis was due to pneumococcal infection. Complement 3 and CH50 values of the proband and her brother were low, while her parents were normal. The patient was given polyvalent pneumococcal and anti-haemophilus vaccines plus ceftriaxone. Recovery was complete after 15 days of antibiotic therapy. This is the first description of a case of recurrent meningitis with C3 and CH50 deficiency in a Turkish family. [Indian J Pediatr 2002; 69 (7) : 625-626].