Fine-needle aspiration biopsy is recommended as the first and most important step in the management of nodular thyroid disease. A retrospective study of 520 patients with nodular thyroid disease was done in the north of Jordan, between January 1998 and August 2001. We compared the results of fine-needle aspiration biopsy (FNAB) of thyroid gland with postoperative histological findings. The results are classified into three groups A)-benign, B)-malignant, and C)-suspicious as shown in table II. The results of the FNAB were benign in 96.4% of the cases which include benign colloid nodules (325 cases), multi-nodular goitre (70 cases), diffuse goitre (40 cases), thyroiditis (23 cases) and thyroid cysts (43 cases). A total of 52 patients underwent surgical management, 49 patients found to be accurate with the FNAB. The accuracy of FNAB was 94% (49 patients out of 52), with a specificity of 99% and a sensitivity of 93%. Ultrasound findings showed that 65% (338 patients) had solid nodules, 15% (78 patients) had cystic lesions and 20% (104 patients) had mixed echogenicity lesions. Histological confirmation of malignancy was 10 out of 11 patients with a 91% accuracy rate. FNAB was found to be a highly effective procedure, which can obviate a lot of unnecessary surgery in case of thyroid lesions, and avoid over treatment of benign disease. Surgery was recommended in all suspicious cases. FNAB under ultrasound guidance increases the sensitivity rate which can reach 100%. FNAB accuracy seems to be similar in cold and in hot nodules. Clinically, most of the patients with benign colloid nodules were having goitres suggesting the role played by iodine deficiency is which a prominent feature in that area in Jordan.