Subclinical hypothyroidism does affect fertility. The prevalence of subclinical hypothyroidism is 10-15 times more common in women than in men. Chemical elements, including trace elements, play important roles in thyroid function and fertility. The aim of this study was to evaluate whether significant difference of chemical element contents exists between female and male thyroids and how they can be related to the etiology of subclinical hypothyroidism. Thyroid tissue levels of twenty chemical elements: Al, B, Ba, Br, Ca, Cl, Cu, Fe, I, K, Li, Mg, Mn, Na, P, S, Si, Sr, V, and Zn were prospectively evaluated in 105 healthy persons (33 females and 72 males). It was found that for ages before 40 years means of Al, B, Ca, Cu, Fe, Li, Mg, S, and Zn content in female thyroid were lower than those in male thyroid. For ages over 40 years means of Ba, Br and Si content in female thyroid was higher whereas mean of Mg content was lower than those in male thyroid. Thus, inappropriate content of intra-thyroidal Al, B, Ba, Br, Ca, Cu, Fe, Li, Mg, S, Si, and Zn can be associated with the etiology of female subclinical hypothyroidism.