Small bumps with pus spots inside the hair may be caused by folliculitis, eczema, seborrheic dermatitis and so on. 1. Folliculitis: when the patient’s hair inside the long pimples with pus spots may be caused by folliculitis, mainly by bacteria, fungi and other pathogens caused by infection, but also may be related to the body’s immune function, allergic reactions, mite parasites, etc., the patient will appear red, swollen, painful, serious pus, broken and so on. 2. Eczema: the disease is mainly caused by a variety of internal and external factors caused by the superficial dermis caused by epidermal inflammation, resulting in patients appearing inside the hair with small pimples with pus spots, accompanied by itching symptoms. 3. seborrheic dermatitis: the disease is mainly related to sebum secretion abnormalities, immune factors, Malassezia infection, epidermal inflammation damage, patients will appear inside the hair long pimples with pus spots, will be attached to greasy scales, and accompanied by itching symptoms. It is recommended that patients go to the hospital in time, under the guidance of the doctor to take targeted treatment. At the same time, we should pay attention to keep the local clean, avoid the use of irritating shampoo products, so as to avoid the recurrence of the situation.