Objective To observe the clinical effect of combination of traditional Chinese and western medicine to treat the hypothyreosis disease, and dosage reduction of thyroid hormone and improvement of thyroid function. Method The patient of hypothyreosis were divided into two groups, 32 cases in treatment group and 30 cases in control group. Both groups were treated with thyroid hormone. The treatment group reduced the dosage of thyroid hormone to high limit in the prerequisite of ensuring the curative effect, and was given the decoction of warming Yang and benefiting Qi, removing stasis and dampness. Then compare the improvement of main clinical symptoms of the two groups, as well as their function of thyroid and side effects of hormone. Result There was no significant difference in total effective rate between two groups, while there was notable diffenrence in excellent effective rate. Compare with the control group, the symptoms of the treatment group were improved obviously and rapidly, the falling extent of the increasing thyroid-stimulating hormone (TSH) was large and quick, so as the enhancing extent of the decreasing T3 and T4, the sid effect of hormone was eradicated. Conclusions To treat the hypothyreosis disease, combination of traditional Chinese and western medicine can improve the symptom quickly, promote the recovery of thyroid function, and get the satisfactory curative effect, even if reduce the dosage of hormone.