There are several possible causes of bunion pain in one foot: First, gout. Most patients with gout have bunion pain as the first symptom, often accompanied by skin redness and swelling, increased skin temperature, and in severe cases, gout stones. Second, tumors, when the bones or soft tissues of the big toe tumors, can also appear bunion pain, then we should conduct relevant nuclear magnetic or X-ray examination for early diagnosis and treatment. Third, tuberculosis can also cause pain in the joint of the big toe when there is tuberculosis, and an MRI, X-ray, or CT examination should be performed for early diagnosis and treatment. Fourth, toe neuritis or toe neuroma. Pain can also occur when there is inflammation or tumor in the toe nerve of the big toe, which should be diagnosed by early physical examination.