In order to combine the diagnosis and treatment guidelines for chronic obstructive pulmonary disease (COPD) with medical knowledge of electronic medical records, a semiautomatic construction method for knowledge maps of chronic obstructive pulmonary disease was proposed. First, the schema concept layer is designed in a top-down manner for the diagnosis and treatment of chronic obstructive pulmonary disease. Knowledge is removed from the data in the electronic medical records of the China-Japan Friendship Hospital. Knowledge extraction of unstructured data is based on the conditional random field (CRF) combined with the symptom dictionary method, through the design of the experiment to extract disease symptoms, verified the accuracy and effectiveness of the design, and stored the knowledge of chronic obstructive pulmonary disease to Neo4j.