Age spots and flat warts can be initially distinguished by the age of the patient, the location and appearance of the lesion, etc. A definitive diagnosis needs to be made by a specialized doctor through dermatoscopy and pathological examination. 1. Age of onset Age spots are more common in the elderly; flat warts are more common in children and adolescents. 2. Location and appearance of lesions Age spots are known as seborrheic keratosis, which refers to some flat, slightly elevated plaques on the skin, the color is usually light brown, brown, black, painless and itchy, mostly in exposed areas such as the face, forehead and the back of the hands, and so on. Flat warts are benign skin growths caused by human papillomavirus infection, warts of unequal size, round, oval or polygonal, the border is clear, showing normal skin color, pink or light brown. The patient is usually not conscious of the symptoms, some patients will feel a slight itching symptoms, mostly in the end of the limbs. 3. Dermatologic examination In addition to the above symptoms, to determine whether it is age spots or flat warts, you need to go to the hospital and ask a professional dermatologist to determine through dermoscopy and pathological examination. It is recommended to consult a doctor for examination and judgment when skin growths appear, and not to treat them on your own.