Siddha system is one of the oldest method of medicine in India.Many diseases are emerging as a trend of lifestyle modifications due to stress, sedentary lifestyle and food habits one among them Hypothyroidism. Hypothyroidism is one of the most metabolic causes of reversible cognitive impairment. Women are five to eight times more likely than men to have thyroid problems. One woman in eight will develop a thyroid disorder during her lifestyle. Siddha system rests on the conceptual framework formed by 96 thathuvams which includes Muthodam ( Vali,Azhal,Iyam).These are vital life-forces govern the physical,physiological and psychological components of an individual thus forming the individual Yakkai ilakkanam (Body constitution). The main objective of the study is to evaluate the incidence of KuraiveethanaNoi(Hypothyroidism) with respective body constitution. This study is conducted in National Institute of Siddha, Chennai with IEC approval. I had selected 100 hypothyroidism (Kuraiveethana noi ) patients with thyroid function test report to analysis the body constitution of Kuraiveethana noi. The study details were collected in the data collection form (Questionnaire).Result of the study is kabavatha thegi patients are more affected in hypothyroidism (Kuraiveethana noi).