In this cross-sectional study, we investigated the associations between patient communication self-efficacy and self-reported symptoms in doctor–patient communication, as perceived by patients, and the mental health and illness of hospital outpatients. Using data from a sample of 74 outpatients (mean age = 37.58 years, standard deviation = 12.54), a structural equation model was calculated. The results showed that communication self-efficacy and respectful behaviour were associated with mental health and illness. Furthermore, self-reported symptoms were correlated with mental illness. Gender and educational differences also occurred. The findings suggest that enhancing patients’ communication skills could benefit outpatients in general, but female and less educated patients in particular.