Pimples on the ankles may be caused by mosquito bites, or due to allergic dermatitis, eczema, tinea pedis and other skin diseases. 1. Mosquito bites: Mosquito bites on the ankle can lead to skin damage, rash, swelling and itching, etc. After the swelling disappears, there may be pimples left on the localized skin of the ankle. 2. Allergic dermatitis: after contact with animal allergens or chemical allergens near the ankles, some patients will have allergic reactions, with erythematous papules, and some patients may have localized blisters and oozing and other symptoms. 3. Tinea pedis: If the skin near the ankle is infected with fungus, tinea pedis may appear, manifesting as severe itching, erythematous pimples as well as small blisters, flaking and other symptoms. Pimples on the ankles need to be examined by the dermatology department of the hospital in a timely manner, after clarifying the cause of the disease to carry out the appropriate treatment, the patient needs to closely observe the change of the condition in daily life, avoid scratching and skin irritation, pay attention to the local skin cleanliness.