This is a case of Hashimoto's thyroiditis with complication of insufficient thyroid function. TCM diagnosis shows patient has liver qi stagnation which causes heat and dampness in liver and gall bladder meridians, and further becomes qi deficiency. Therefore, we prescribe JiaWeiXiaoYao powder and ChaiHuShuGan powder to sooth the liver and relieve qi stagnation. HuangQi is used to replenish qi, YuJin to relieve stagnation and promote circulation, YinChen to clear heat and resolve dampness, and GeGen to dispel pathogens in the muscles. The patient is referred to the department of metabolism to have further examination. The blood test shows idiopathic hypothyroidism caused by autoimmune problems. He is suggested to have a combination of conventional and TCM treatments. Hypothyroidism usually belongs to ”deficiency” syndromes in TCM, and often manifests in deficiency in spleen and kidney yang. However, this case shows liver qi stagnation with heat and dampness in liver and gall bladder meridians. Since it's a rare case, we provide the case study for future research reference.