Most frequent Round Cell Tumors are Non-Hodgkins Lymphoma, Neuroblastoma, Ewing/PNET and Rhabdomyosarcoma. Neuroblastoma, Retinoblastoma, Wilms Tumor, Hepatoblastoma show presentation in early childhood while Rhabdomyosarcoma is seen throughout childhood. The majority of round cells tumors have male predominance. Identification and accurate diagnosis of a tumor is an art and necessiates complete knowledge of cellular, biochemical , molecular events and pathogenesis of the tumor. Round cell tumors are characterised by round and relatively undifferentiated cell. Differential diagnosis of round cell tumors is difficult due to their undifferentiated or primitive character, those tumors that shows good differentiation are generally easy to diagnose .The ubiquitous distribution and diverse histology of different round cell tumors pose a challenge in their diagnosis. The diagnostic aids like the use of special stain, immunocytochemistry, flowcytometric, immunophenotyping, and reverse-transcriptase polymerase chain reaction are extremely useful in cases when tumors are undifferentiated and distinction is not possible on morphological basis alone.