We have experienced 2 cases of MRSA infection. Case 1: A 16 month-old girl, whose underlying disease was VAHS, had chronic sinusitis. MRSA was isolated from the blood and rhinorrhea. Her sinusitis was very intractable and it was difficult to eradicate MRSA from the nare. Case 2: A 6-months-old girl was admitted to our hospital with urinary tract infection. She had an ectopic uretelocele. Partial nephrectomy and uretectomy was performed. Retroperitoneal and intraperitoneal abscess had recurred three times during 17 months after the first operation. This abscess was slowly progressive and MRSA was very difficult to eradicate. These 2 cases showed characteristics of MRSA infection.