Psychodermatology is an underappreciated field that studies psychocutaneous disorders, which are conditions that have both dermatologic and psychiatric characteristics. Underlying psychiatric comorbidity is estimated to occur in up to one-third of dermatologic patients, and psychiatric illness may either be the cause or the consequence of dermatologic disease. The present work aims to identify the type and frequency rate of infectious skin diseases among patients with psychiatric diseases. 500 patients with primary psychiatric disorders and 199 healthy controls from the Benha City, Qalyubia Governorate, Egypt were included in the study and were diagnosed according to The Diagnostic and Statistical Manual of Mental Disorders (DMS V) Criteria. A specially designed questionnaire including socio-demographic data , dermatological and general medical examination was applied. The data were statistically analyzed. There was a significant statistical increase in the prevalence of infectious skin diseases in psychiatric patients compared with non-psychiatric patients. Health education of psychiatric patients and/or of their caregiver and periodic monthly inspection of psychiatric patients  are highly indicated for the prevention and control of infectious skin diseases in these  patients.