Purpose: Diagnosis of thyroid cancer through clinical , ultrasound , FNA and histopathology. Material and Methods : Conducting research on patients who were diagnosed thyroid cancer, surgical treatment at the ENT national hospital and ENT Department of Bach Mai Hospital from 2007 to 2013 . Results:The mean age 42.75 + or - 1.39 years old. The percentage of female / male : 4.1 / 1. The most common hospitalized period of 1 year after the first symptoms appear (77.4 percent). Reasons for detecting disease: swelling that blocks the neck (64.7 percent), accidental detection (6.9 percent). Common functional symptoms: self visible and palpable swelling of neck mass (64.7 percent), swallowing difficulties (30.4 percent), hoarseness (12.7 percent). Examination in TG tumors hard, sure (94 percent), no clear boundaries (11 percent), less mobile (10 percent). Physical examination revealed cervical lympho nodule (16.7 percent). Restrictions and/or fixed ipsilateral vocal cord tumors (10.8 percent). Neck ultrasound: hypoechoic mass (87.2 percent), micro calcification in tumors (70.6 percent), no clear boundaries (56.9 percent), ultrasound shows cervical lymphadenopathy (21.6 percent). FNA: positive rate is 72.5 percent. Histopathology: differentiated thyroid cancer (99 percent), the most common papillary 95.1 percent, followed by follicular 4/102 patients (3.9 percent). Conclusion: The symptoms suggestive of thyroid cancer: thyroid tumors is diagnosed firm, not clear boundaries, less mobile, palpable cervical lymphadenopathy, restrictions and/or fixed ipsilateral vocal cord. Neck ultrasound shows hypoechoic mass with microcalcification, not clear boundaries, ultrasound shows cervical lymphadenopathy, FNA is answered thyroid cancer. Results histopathology can accurately answer thyroid cancer.