Hair loss in one area is commonly associated with baldness. Patch baldness is a psychiatric-driven, autoimmune-related, non-scarring hair loss disease. It is mainly found on the scalp, but can also be generalized to the whole body. The cause of the disease is still unclear, and it may be related to genetic factors, psychiatric factors, endocrine factors, and immune-inflammatory factors. Typical symptoms will be manifested as the sudden appearance of round or oval areas of hair loss with clear boundaries, and the affected area has smooth skin without inflammation, scaling, or scarring. In addition to patchy baldness, hair pulling fetish and other diseases can also cause localized hair loss. It is recommended to go to the hospital first to confirm the diagnosis, and follow the doctor’s instructions for treatment.