The related theory of constitution and disease in Shanghan Lun(Treatise on Cold Pathogenic Diseases) and Jingui Yaolve(Synopsis of Golden Chamber) are analyzed,including constitution and disease occurrence, constitution and disease tendency, constitution and disease transmission, constitution and disease treatment, constitution and disease prognosis. It is considered that disease occurrence is closely related to the normal state of promordial qi in five viscera,disease tendency is closely related to the age,sex and strength of vital qi；constitution differences can lead to different trends in transmission；in the disease treatment,especially the therapy of expelling pathogen such as diaphoresis and purgative method,different compatibility and dosage should be adopted according to the constitution differences；the key to determine the disease prognosis is the strength and weakness of constitution and the rise and fall of vital qi.