Red bumps on the face that are itchy and hot may be related to solar dermatitis, contact dermatitis, allergic dermatitis and other factors. 1. Solar dermatitis: This is an inflammatory reaction caused by overexposure of the skin to ultraviolet rays, and the affected area of the skin will have obvious redness, swelling, burning and pain, and there will be bright red red spots or bumps after sun exposure. 2. Contact dermatitis: this is an inflammatory skin disease caused by skin contact with external substances, may be in contact with animal hair, feces, feathers, and may also be in contact with plant flowers, leaves, fruits, etc., which induces localized red bumps, accompanied by itching, burning and other symptoms. 3. Allergic dermatitis: this is a common skin disease caused by contact with allergen stimulation, allergens will enter the body through skin contact, inhalation, food or injection and other ways, which causes a series of reactions, such as red bumps on the face, itching and burning, and so on. If the phenomenon of red bumps on the face is very itchy and hot, it is recommended to go to the hospital and cooperate with the doctor for examination and treatment.