The total endoprosthesis replacement of the tibia – is extremely rare operation, even in adults. for children of preschool age, as a rule, the amputation was standard of surgical treatment in total or subtotal tumor lesion of the tibia. In department of general oncology of pediatric oncology and hematology institute of N.N. Blokhin russian Cancer research Center we spent an attempt to perform limb salvage surgery with delayed endoprosthesis in a child 5 years old with osteosarcoma of the tibia. The article with our case report describes a unique operation – subtotal resection of the right tibia with replacement spacer of the defect from the bone cement made in our institute. descriptions of these operations in a child of this age, we have not found in the current literature.