This paper aims to introduce Professor Li Yan’s clinical experience in using yang-warming therapy. Professor Li think yang qi is the energy root to maintain physiological activities and viscera functions of human body, which can determine the reproduction, growth, development, aging, and death of human. There is a saying goes like ”Yang qi nourish one’s life, and without it, one may perish.” Yang deficiency syndromes are often characterized by fear of cold and chills limbs, puffy face and feet swelling, sloppy stool, clear copious urine or edema of urinary bladder, pale and puffy tongue, white and smooth fur and faint deep pulse. So yang-warming therapy supplement the body from two aspects, one is warming yang to expel cold, and the other is transforming qi to increase urine. This essay listed the typical cases that applied warming-yang therapy to interpret professor Li Yan’s TCM theory and thinking pattern.