Why do I have pimples all in my ears?

You can develop a pimple in the ear’s cartilage or a pimple in the ear canal—it’s still skin and it can become clogged if proper hygiene isn’t observed. Talk to your doctor if you believe your recurring pimples are because of a hormonal imbalance.
Stress: Learn how to cope better with stress in your life by meditating, doing yoga, or talking to someone you trust about what’s going on. A short 30-minute walk can also clear your head and lower blood pressure.
Allergies: An allergic reaction to cosmetics, medicines, and vitamins can cause pimples inside the ear and elsewhere.
Diet: Greasy, fast food, processed foods, and foods with many additives can wreak havoc on the body and the lack of nutrition may exhibit itself in the form of acne. Try to eat nourishing, natural foods to get the vitamins and minerals your body needs, including fresh fruits and vegetables, lean meats, grains, nuts, and dairy.
Helmets: These can cause pimples in the ear because of the pressure applied when the helmet is rubbing against the ears. Wash the inside of the helmet with a face wipe or a cloth with some soap and hot water. Pay particular attention to the areas around the ears. And be sure to clean it each time someone other than you uses the helmet.