Rickets is a nutritional disorder which is caused either by deficiency of vitamin D or by a defective activation of vitamin D. In these days, even though the incidence of rickets has decreased through adequate nutritional support, we sometimes experience rickets in babies receiving a prolonged special diet as therapy for chronic diarrhea, or those subject to a in receiving the prolonged elimination of milk because of allergy. But there are no reports about rickets caused by absolute elimination of milk because of allergies in Korea. We report here a case of rickets developed after feeding on Sunsik(a mixture of several grain and fruits powder) during a seven months period in an 8-month-old male patient. This male infant manifested vomiting, poor feeding, decreased serum calcium and 25- hydroxycholecalciferol levels, and markedly increased serum alkaline phosphatase and parathyroid hormone levels. Skeletal X-rays showed cupping and fraying in distal metaphyses of radius and ulna, and generalized osteopenia. The patient improved with vitamin D and calcium therapy.