A 67-year-old female was admitted to our hospital with eruption and cervical lymphadenopathy which occurred one week after pneumococcal vaccination. Polyclonal hyperimmunoglobulinemia (IgG 6,620 mg/dl) and mild plasma cell proliferation (6.4%) in a bone marrow specimen were found, but a lymph node aspiration biopsy showed no specific findings. Normochromic and normocytic anemia with a positive direct Coombs test were also confirmed. Short-term intensive steroid therapy was given, but the systemic eruption and lymphadenopathy continued. About 4 months after vaccination, she suffered from edema in her face and legs and visual disturbance. When massive proteinuria (10.4 g/day) was found, she was admitted to our ward. A renal biopsy specimen showed a minor glomerular abnormality with mild interstitial plasmacytic infiltration. An abdominal CT scan showed hepatosplenomegaly and para-aortic lymphadenopathy. Uveitis was also found by ophthalmoscopy. These abnormalities completely disappeared after intensive steroid therapy including pulse therapy. On the basis of her clinical course and laboratory findings, it was suggested that minimal change nephrotic syndrome might be induced after vaccination, possibly due to hypersensitivity syndrome.