Objectives: This study was done to determine the diagnostic efficacy of fine needle aspiration cytology (FNA), frozen section biopsy (FSx) and ultrasonography in a palpable thyroid mass. Materials and Methods: During the period from July 1999 to March 2002, the medical records of 98 patients who underwent a thyroidectomy for thyroid mass, at the Department of Surgery, Chonbuk National University Hospital, were reviewed retrospectively. Ninety eight cases were classified according to whether the FNA cytological diagnosis inadequate, benign, suspicious, or malignant and the FSx diagnosis benign or malignant and the ultrasonographic examination was benign, suspicious, or malignant. The diagnostic correlations of ultrasonography, FNA cytology, frozen section, and both FNA cytology and frozen section with definite histologic diagnosis were evaluated. Results: According to the FNA cytological interpretation, 76 cases were diagnosed as benign, 6 cases suspicious, 13 cases malignant, and 3 cases inadequate. The sensitivity and specificity for FNA were 86.3% and 95.9% and for FSx 95.5% and 100% respectively. The diagnostic accuracy of FNA and FSx were 93.5% and 98.9% respectively. Based on a definite histologic diagnosis, the ultrasonographic examination had a sensitivity and a specificity of 77.2% and 78.9%. Conclusion: The results confirm that FNA cytology is a reliable and useful tool in the initial evaluation of a palpable thyroid mass compared to the ultrasonographic examination. Intraoperative FSx is a valuable diagnostic procedure to confirm the cytological diagnosis with undetermined or unsatisfactory cytological diagnosis.