Anal fistulas and hemorrhoids are two different types of common colorectal diseases; neither can be said to be more severe than the other, as the severity of each disease depends on its progression and extent. If it's a simple superficial anal fistula, the severity is generally mild, primarily treated with surgery. However, if a high, complex anal fistula is present, in addition to surgery, a comprehensive pelvic MRI examination is also required to rule out any infections in the deep sphincter and ischioanal fossa. The severity of hemorrhoids primarily involves circular mixed hemorrhoids, or those accompanied by incarceration. If circular mixed hemorrhoids with incarceration occur, it is advisable to undergo surgical treatment as soon as possible to avoid necrosis. If hemorrhoids result in persistent and significant rectal bleeding, surgery should also be performed promptly to prevent anemia in the patient.