There are two types of anal fissures in Crohn’s disease (CD): i. Primary anal fissures are not related to Crohn’s disease and the appearance of the lesion does not differ from that of a normal anal fissure, with the typical features: shallow ulcers, located in the median line, extending from below the dentate line to the outer edge of the anal canal. The following treatments are usually effective: sitz baths, narcotic and hormonal ointments, and diarrhea control. Primary anal fissures are rare in patients with Crohn’s disease. Idiopathic fissures associated with CD CD fissures are characterized by deep, wide and sometimes multiple ulcers, often located laterally, away from the median line and often associated with other perianal disease. Although these fissure lesions may appear severe, they are usually asymptomatic or mild, and the literature reports that 40% to 85% of CD fissures are painful in combination. 80% or more of CD fissures heal spontaneously. If active perianal CD is present, oral metronidazole, 5-aminosalicylic acid enemas or anal suppositories may be administered, and immunosuppressive agents may also be considered. If anal fissures cause pain, attention should be paid to the presence of abscess or fistula formation. If the anal fissure does not heal and the symptoms persist, the possibility of proctitis needs to be excluded. CD fissures should not be treated with anal fissure excision. Simple fissures with high anal canal pressure and no rectal inflammation may be effective for internal sphincter lateralization. Most fissures that do not heal with medical treatment can be cured by internal sphincter laparotomy if they are not associated with proctitis. If internal sphincterotomy is not performed, an abscess or anal fistula may eventually form. Surgery should be avoided if proctitis is also present. Some patients with CD may develop a specific type of anal canal ulcer that is wide and penetrating, involving most of the anal canal, even in a circular pattern, and is ineffective for conventional local treatment. Large ulcers forming cavities often cause severe perianal pain, with up to 56% of patients having severe persistent pain and 35% having painful defecation. Local treatment such as granulation debridement and local injections of glucocorticoids (along with oral azathioprine) may be effective, but these patients often eventually require rectal resection and fecal diversion.