Objective:Thyroid nodules is common clinical problems. The purpose of study is to evaluate the frequency of malignancy in both sexes, in different age groups and comparison of different types of carcinoma, which occur in cold nodule. This study will help in highlighting the significance of such a finding and help towards establishing a treatment protocol applicable to our setting. Study Design: Descriptive Study. Place and Duration of StudY:Surgical Ward II, Jinnah Post-graduate Medical Center (JPMC) Karachi (from Sept 2006 to August 2008). Patients and Methods:It is a descriptive study including 65 patients with cold nodule thyroid, during a period of two years from September, 2006 to August, 2008, conducted in the Department of General Surgery, Ward-2, Jinnah Postgraduate Medical Centre, Karachi. The patients presented in surgical outpatient department with solitary thyroid nodules were advised thyroid scan. The patients in which thyroid scan shows cold nodule were further evaluated. Results:Out of 65 patients with cold nodule, 47 (72.3%) patients had simple colloid goitre, 7 (10.76%) patients had follicular adenoma, 1 (1.5%) patient had thyroiditis, 5 (7.69%) patients had papillary carcinoma, 2 (3.07%) patients had follicular carcinoma and 1 (1.5%) patient had medullary carcinoma. The frequency of malignancy in cold nodule thyroid was 12.3%.All the patients with thyroid carcinoma were ultimately treated by total thyroidectomy and postoperative thyroxine and radioactive iodine therapy was advised. Conclusion:The frequency of malignancy in cold nodule thyroid was 12.3% in this study. Different types of thyroid carcinomas found in this study are; papillary carcinoma 62.5%, follicular carcinoma 25% and medullary carcinoma 12.5%. In this study, thyroid carcinomas are found commonly in middle aged group and more frequently in females. No recurrence or metastasis found in the follow-up period. Hence this study recommended the total thyroidectomy as a procedure of choice for thyroid carcinoma.