A perianal cyst is a cystic mass around the anus with a long history, a shallow lesion with an intact cystic wall, and no direct association with the anus. When infection occurs, redness, swelling, and pain can occur. Sebaceous cysts include sebaceous cysts and epidermoid cysts. Sebaceous cysts are retention cysts caused by obstruction of sebaceous gland excretion and are mostly found in areas with dense sebaceous gland secretion, such as the head, face, and back, where small black spots of sebaceous gland openings can be seen on the surface. Epidermoid cysts are caused by the entry of epidermal basal cells into the subcutaneous growth due to obvious or obscure trauma. The wall of the cyst is composed of epidermis and the cyst will be keratinized with scales. They are most often found in areas prone to trauma or abrasion, such as the buttocks, injection sites, or elbows. Perianal cysts can be surgically removed, but the surgery is required to remove the cyst wall, otherwise they are prone to recurrence.