Given the role of congeniality in interpersonal communication, congenial people can experience better relationships, including friend relationships, roommate relationships, marriage relationships, and business cooperation. However, in the medical field, it is worth further exploring whether congeniality can have similar benefits. From the perspective of similarity interpersonal attraction theory, this study explores the influence of doctor-patient personality similarity on doctors’ economic returns, as well as the moderating effects of doctors’ titles and patients’ disease types. This study takes mHealth services as the research context, extracts the personality traits of both doctors and patients from the doctor-patient interaction text. The results show that (1) doctor-patient personality similarity has a positive impact on the doctor’s economic return; (2) the doctor’s title and the patient’s disease type play a important role in moderating effect on the relationship between doctor-patient personality similarity and the doctor’s economic return. The results of this study verify the feasibility of extracting personality traits from doctor-patient interaction text and enrich the application of similarity interpersonal attraction theory in mHealth services.