The thyroid gland is a small organ that’s located in front of the neck, wrapped around the windpipe (trachea). The thyroid secretes two essential hormones T3 - Triiodothyronine & T4 – Thyroxine, collectively called thyroid hormones. Their secretion is under the control of TSH from Pituitary and TRH from Hypothalamus. During infancy and childhood, adequate thyroid hormone is crucial for brain development. The prevalence of hypothyroidism in developed countries is around 4-5%, whereas it is about 11% in India. It is more common in women than in men. Hypothyroidism has multiple etiologies and manifestations. The most common clinical manifestations are weight gain, loss of hair, cold intolerance, lethargy, constipation, dry skin, and change in voice. The signs and symptoms of hypothyroidism differ with age, gender, severity of condition, and some other factors. The diagnosis is based on clinical history, physical examination and serum level of FT3, FT4, and TSH (Thyroid-stimulating hormone), imaging studies, procedures, and histological findings. The description of hypothyroidism as a disease is not directly found in Unani texts. However, the signs and symptoms of hypothyroidism resemble the clinical manifestation associated with Su-e-Mizaj Barid Maddi (derangement in cold temperment). These observations from Unani literature describe derangement in cold temperament and relate them to the clinical presentation of primary hypothyroidism in conventional medicine. Increasing dosage and continuous medicine make the patient drug dependent till the end of the life. Even after years of treatment, it is associated with failure to provide relief in clinical manifestations. Moreover, excessive thyroid hormone replacement carries the potential for serious long‑term metabolic complications (e.g.,accelerated osteoporosis). In the USM, the main emphasis of the principle of treatment (Usool-e-Ilaj) is to correct the abnormal constitution (Su-e-Mizaj) and alter the six prerequisites for existence (Asbab-e-Sitta Zarooriya) to restore normal health. It is a packaged treatment, that is, different components of treatment are given as a package form which includes correction in diet, different drugs, dosages form, and regimens. Due to certain limitation and associated side effects, this conventional medicine has certain limitations, which can be overcome by using unani herbal formulations either in single form or compound form. This unani medicine can limit the subclinical hypothyroidism at its level and prevent it from moving to overt hypothyroidism. The present Research study on “Efficacy of Unani Herbs in Treating Subclinical & Overt Hypothyroidism” was conducted on 10 patients from either gender whose TSH value was above normal (> 4.5ng/dl). They were divided in two groups of 5 patients each and was treated with separate group of medicine A & B. They were under observation for nearly 2 months. It was elicited that this disease effects the female most and of cold temperment. This research study ultimately concluded that Group A medicine has better response than Group B medicine with a 60% Cured, 20% Partial response & 20% No response. Group B also showed response but with efficacy lesser than Group A.