We often see cases of angular cheilitis, which occurs when there is inflammation at the corners of the mouth. There are many causes of angular cheilitis, including local irritation such as rubbing the corners of the mouth incorrectly or frequently licking them, as well as a lack of nutrients. A main cause of oral inflammation is a deficiency in vitamin B2, along with infectious factors, and the presence of bacteria and viral microbes. Candida albicans is a common fungal infection in angular cheilitis, along with other factors such as emotional stress, anxiety, mental factors, and immune genetic factors, all of which can lead to angular cheilitis. Therefore, it is important to pay attention to promptly supplementing needed nutrients, eating plenty of fruits, vegetables, and vitamin-rich substances. At the same time, maintaining a good mental state and eliminating irritants in the mouth can help in returning to normalcy.