Abstract: The International Classification of Childhood Cancer(ICCC)is used to group histologic types and sites into meaningful categories for childhood cancers, which reflects characteristics of childhood cancers. The classification of childhood cancer is based on tumor morphology and primary site with an emphasis on morphology rather than the emphasis only on primary site in the adults's classification system. ICCC is based on the International Classification of Diseases for Oncology and contains 12 main diagnostic groups and 48 subgroups. The appropriate application of this system is the base to conduct childhood cancer monitoring and researches, including etiology, treatment and survival researches for childhood cancer. It will improve the practice of childhood cancer prevention and control.