Itchy outer skin of the eyes may be related to eczema, mosquito bite dermatitis, contact dermatitis and other causes. 1. Eczema: If eczema occurs on the outer skin of the eye, it can cause redness, swelling, itching and other symptoms. 2. Mosquito bite dermatitis: If the outer skin of the eyes is bitten by mosquitoes, the mosquito saliva contains acidic substances into the body to produce an allergic reaction, which can cause the outer skin of the eyes itchy. 3. Contact dermatitis: if the eye cream and other skin care products contain allergenic substances, can cause itching of the outer skin of the eyes. It is recommended that people with itchy eyes go to the hospital in a timely manner, to clarify the cause of the disease, under the guidance of the doctor for standardized treatment, so as not to delay the condition of the body to bring adverse effects.