Itchy face with pimples when scratching may be caused by hives, eczema, insect bite dermatitis and other diseases. 1. Urticaria: patients with allergic constitution may cause urticaria by contacting or inhaling or ingesting substances that are easy to induce allergy, resulting in itchy facial skin and localized pimples when scratching. 2. Eczema: the occurrence of eczema is related to a variety of factors, such as external stimuli, mental stress, genetic factors, may lead to itchy skin, scratching may appear pimples, papules, erythema. 3. Insect bite dermatitis: an allergic reaction caused by mosquito bites, resulting in itchy skin, bumps and even blisters when scratching. It is recommended to find and get rid of the allergens, go to the dermatology department of the hospital for examination if necessary, and give appropriate medication with the doctor’s advice.