A pimple on the head that hurts when pressed may be due to scalp folliculitis, seborrheic dermatitis, contact dermatitis and other factors. 1. Scalp folliculitis: this is an inflammatory skin disease mainly involving the scalp follicles, which may be triggered by squeezing, scratching and rubbing the scalp, and red follicular inflammatory papules will appear, accompanied by itching and pain, and usually do not pay attention to scalp cleanliness, immunity is low. 2. Seborrheic dermatitis: also known as seborrheic eczema, belongs to the more common chronic inflammatory skin diseases, usually occurs in the head, face, chest and back and other seborrheic parts, often accompanied by pain and varying degrees of itching. 3. Contact dermatitis: this is due to contact with external allergens stimulation and caused by the situation, may occur in any part of the body, including the scalp, accompanied by significant itching, scratching and stimulation will have pain and other symptoms. It is recommended that after the symptoms of a pimple on the head and pain when pressed, the patient should cooperate with the doctor as soon as possible for examination and treatment after determining the cause.