Objective To discuss theoretical structure model for the scale of recurrent oral ulcer (ROU) with traditional Chinese medicine characteristics; To lay a theoretical foundation for further developing scale. Methods This study followed international patients reported outcome (PRO) scale development specification, combined TCM theories, including the theory of mouth dominate and five internal organs correlation, uniformed spirit and body, correspondence between human and the universe, seven emotions, constructed theoretical structure of PRO scale of ROU. Results The theoretical structure of PRO scale of ROU included four major areas as physiology, psychology, independence, and society and nature. Conclusion Theoretical model of PRO scale of ROU laies the foundation and provides the oretical guidance for the formulation of PRO scale of the ROU.