Red blisters on the roots of pubic hairs are considered to be related to diseases such as genital herpes, eczema and contact dermatitis. 1. Genital herpes: the disease occurs around the genitals, such as labia, foreskin and other places, the patient will appear blisters, erythema and other symptoms. The cause of this disease is mostly related to herpes simplex virus invading the body, alcoholism, cold, decreased resistance and other factors may also trigger the disease. 2. Eczema: Eczema can develop on all parts of the body surface, commonly found on the hands and feet, head and face and pubic area, mostly manifested as erythema, papules, blisters and other symptoms. The cause of this disease may be related to systemic diseases, heredity, immunity and so on. 3. contact dermatitis: this disease is mostly related to the body contact exogenous material stimulation of the skin, lesions can spread or involve the surrounding areas, lesions are mostly manifested as a clear border of erythema, papules and blisters. The reason for the red blisters at the root of the pubic hair is not the same, it is recommended that the patient go to a regular hospital to clarify the cause of the disease.