To explore the origin and development of Hunan Ouyang’s clinical thinking on Miscellaneous Diseases.The founder of Hunan Ouyang’s miscellaneous diseases genres emphasized on both cold and warm syndromes and used comparative analysis.The first generation of its successors developed a triple therapy of diagnosis and treatment by combining disease,syndrome and symptom together on the basis of clarifying main symptoms with three procedures,differentiation with three types and twenty-one sub-types symptoms and treatment from symptoms.The second generation completed and carried forward the clinical thinking of Ouyang genre by taking effort in clinics and methodology field and proposed principles,thinking pattern and methods in clinical scientific research.