In Head & Neck – Oral cancer the main tools of radiological evaluation are Ultrasound neck, CT scan, MRI scan and PET CT Scan. Ultrasound Neck is the basic test for evaluation of neck nodal metastases and early oral cancer or precancerous lesions like leukoplakia or erythroplakia just need ultrasound evaluation. The site of oral cancer determines which is better CT scan or MRI scan. For buccal cancers since bone involvement is the most important factor which determines the extent of surgery, CT scan is the best investigation to determine the bone involvement. In tongue cancer the depth and extent of soft tissue involvement are important prognostic factors; MRI is the investigation of choice as it gives better delineation of soft tissues.