Hypothyroidism is a common disorder in the population with a female predominance. Most hypothyroidism cases were found in the age group range of 30–35 in both the sexes of individuals but women were more prone to develop it. Disturbance or imbalance in the thyroid hormone levels is the underlying cause of resultant hypothyroidism. A comparative study of serum T3 (triiodothyronine), T4 (thyroxine), TSH (thyroid stimulating hormone), copper, zinc, magnesium and iron was done in 100 normal individuals as controls (Group I). 100 Hypothyroid patients showing Good Response to Levothyroxine Therapy – GRLT as (Group II A) and 100 Hypothyroid patients showing Poor Response to Levothyroxine Therapy – PRLT as (Group II B) over a period of 1 and half year in the age group of 20 to 45 years. The levels of TSH were found to be elevated in hypothyroid patients with relatively lower levels of serum T3 and T4 as per our study conducted in hypothyroid patients with PRLT when compared with the healthy subjects and patients in GRLT group. A study of implementation of levothyroxine therapy in hypothyroid subjects showed improvement in the patients with all the hormone levels returning back to the pre – hypothyroid state in majority of the hypothyroid patients with GRLT in comparison with the controls. Results of the study indicate a significant decreased levels of serum copper, zinc and iron in hypothyroid patients showing poor response to levothyroxine therapy whereas the magnesium levels in the serum of hypothyroid individuals with poor response to levothyroxine was found elevated. The serum levels of all the trace elements studied i.e., copper, zinc, magnesium, and iron in GRLT hypothyroid individuals and controls were within the normal ranges. Further studies are however needed on these parameters for establishing serum levels of trace elements in hypothyroidism in relation to response to levothyroxine therapy.