In the ancient medical books read by Li Shizhen, it is often found that there are many inconsistencies among various schools, and many of them are contradictory. In order to extract its essence, correct its fallacy and make it correct, Li Shizhen adopted the method of going deep into reality and the masses. 10 years, he went away several times, crossed Chung Shan Man, ran to Wan Li Road, took pains to collect the medicinal materials that needed to be studied, personally cultivated, dissected, baked and refined some drugs; At the same time, I also consulted many experienced practitioners, such as doctors, woodcutters and fishermen. So as to identify and verify more than 1000 drugs recorded in past dynasties, so as to eliminate mistakes, preserve the truth and make new scientific conclusions. In Compendium of Materia Medica, he added more than 300 new drugs and more than 8,000 new prescriptions, which enriched the great treasure house of Chinese medicine.