Introduction: Osteosarcoma is very rare, but isthe most common type of bone cancer in children and adolescents. It is most common in teenagers and young adults. Osteosarcoma is a cancer that starts in the bone. The exact cause is unknown. Cancer is caused by changes in the DNA of the cells themselves. After the examination, specialist examinations are performed. Once the diagnosis of osteosarcoma is set, other tests may be performed. This helps health professionals caring for a sick child to learn more about the cancer. In many cases, a team of doctors, nurses and pharmacists work with a sick child and family to provide care for all of them. This is called a multidisciplinary team. Objective: The aim of this paper was to educate about osteosarcoma and to present the case of a child with osteosarcoma. Discussion: The nurse plays a vital role in the care of patients with osteosarcoma. From the very beginning, whenthe disease is being explained to the patient and his family, the nurse provides comfort and support, reinforces and explains the information provided by the doctor. All aspects of medical care are covered, and he / she is often the first line of communication when the patient calls and asks for information or wants to report the problem to the doctor. After processing the child's data from the case report, the nurse comes to several nursing diagnoses that resulted from the health care process: reduced food intake, nausea, reduced ability to perform personal hygiene, reduced ability to dress, pain and fear. Conclusion: Based on the case report and education on osteosarcoma, it can be concluded that osteosarcoma is most common in boys during childhood and adolescence, the difficulties encountered by the child affect the whole family and the approach to treatment must be multidisciplinary.