The malignant neoplasm is called as malignant rhabdoid tumor or renal tumor. The Malignant tumor had the highest rate of proliferation. Tiny, round, and generally undifferentiated cells make up malignant small round cell tumours. A round cell tumor is a group of malignant tumors composed of relatively small and undifferentiated cells with an increased nuclear - cytoplasmic ratio. Soft tissue malignant tumours of the abdomen and pelvis are a rare but serious kind of cancer. Examples of these tumours include Ewing's sarcoma, peripheral neuroectodermal tumour, rhabdomyosarcoma, synovial sarcoma, non-lymphoma, Hodgkin's retinoblastoma, neuroblastoma, and hepatoblastoma. Mast cell tumour, histiocytoma, lymphoma, plasmacytoma, and transmissible venereal tumours are some of the different types of round cell tumours. Melanomas are the cytologic "great impostor," as they might look on cytology as round cell tumours despite being classed as mesenchymal cancers. Rhabdoid tumours have long been thought to be extremely malignant and have a bad prognosis. Children with this form of tumour have a six to eleven-month median survival duration. They're also less common. In 5% of small round cell tumor patients, can be curable, and it is best achieved by combining systemic chemotherapy with thorough cytoreductive surgery. Here we report a 9-year-old female child who was diagnosed with a malignant rhabdoid round cell tumor in the pelvis. She has undergone excision of pelvic floor tumor andfurther managed with Chemotherapy.