Background: Perianal fistulas are a common anorectal pathology. The sphincter-cutting techniques of fistulectomy and fistulotomy are associated with high cure rates for simple anal fistula with negligible risk of incontinence. However, superiority of either technique has not previously been conclusively demonstrated. The aim of this systematic review is to compare outcomes of the two surgical techniques. Methods: A search of MEDLINE, EMBASE and Cochrane Databases for randomised controlled trials (RCT) comparing fistulotomy to fistulectomy for simple anal fistulas was conducted. The primary outcome was healing time; secondary outcomes included operative time, length of hospital stay, post-operative pain score, post-operative complications and fistula recurrence. Results: Thirteen RCTs meet inclusion criteria, comprising a total of 685 fistulectomy and 688 fistulotomy patients. There was no difference between the techniques for healing time (p=0.15), operative time (p=0.13), length of stay (p=0.05), wound infection (p=0.97), flatus or faecal incontinence (p=0.35 and p=0.70, respectively) or recurrence (p=0.19). Post-operative pain at 24 hours, assessed using a visual analogue scale was significantly lower in the fistulectomy group (MD-0.49, 95%%CI:-0.90,-0.08; p=0.02), and we found significantly fewer post-operative bleeding complications in the fistulotomy group (OR3.81, 95%CI:1.23,11.80; p=0.02). Conclusion: This systematic review did not find conclusive evidence of superiority of either fistulectomy or fistulotomy in terms of healing time. The two statistically significant findings of lower post-operative pain scores with fistulectomy, and reduced post-operative bleeding with fistulotomy, may be confounded by the effect of marsupialisation in some studies.